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11 tháng 1 2023

A

11 tháng 1 2023

Uii, c gioi the:))

EXERCISE 1: CHOOSE THE BEST ANSWER:1. That’s my friend,_______________ comes from Japan.A. which B. who C. whom D. where.2. The plants which______________ in the living room need a lot of water.A. are B. be C. is D. was3. She’s the woman_______________ sister looks after the baby for us.A. who B. which C. that’s D. whose4. That’s the doctor for________________ Cliff works.A. that B. which C. whom D. whose5. Marie,______________ I met at the party, called me last night.A. that B. whom C. which...
Đọc tiếp

EXERCISE 1: CHOOSE THE BEST ANSWER:

1. That’s my friend,_______________ comes from Japan.

A. which B. who C. whom D. where.

2. The plants which______________ in the living room need a lot of water.

A. are B. be C. is D. was

3. She’s the woman_______________ sister looks after the baby for us.

A. who B. which C. that’s D. whose

4. That’s the doctor for________________ Cliff works.

A. that B. which C. whom D. whose

5. Marie,______________ I met at the party, called me last night.

A. that B. whom C. which D. whose

6. I remember Alice,______________ rode the bus to school with.

A. I B. whom I C. which I D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

A. where B. when C. which D. that

8. Tell me about the city ______________ you grew up.

A. that B. where C. which D. ø

9. Anna found the book that ________________ wanted at the bookshop.

A. ø B. where C. she D. which

10. Please remember to take back to the library all the books ________ are due this week.

A. ø B. that C. when D. they

11. He likes the dress. Huong is wearing it

A. He likes the dress which Huong is wearing it

B. He likes the dress Huong is wearing it

C. He likes the dress who Huong is wearing

D. He likes the dress Huong is wearing

12. Most of the classmates couldn't come. He invited them to the birthday party

A. Most of the classmates he invited to the birthday party couldn't come.

B. Most of the classmates he was invited to the birthday party couldn't come.

C. Most of the classmates that he invited them to the birthday party couldn't come.

D. Most of the classmates which he invited to the birthday party couldn't come.

13. What was the name of the man? You met and talked to him this morning.

A. What was the name of the man who you met and talked to him this morning?

B. What was the name of the man you met and talked to this morning?

C. What was the name of the man you met and talked to whom this morning?

D. What was the name of the man whose you met and talked to this morning?

14. The church is over 500 years old. Our class visited it last summer.

A. The church which our class visited it last summer is over 500 years old.

B. The church that our class visited it last summer is over 500 years old.

C. The church which our class visited last summer is over 500 years old.

D. The church our class visit last summer is over 500 years old.

15. The song says about the love of two young stdents. She is singing the song.

A. The song which she is singing it says about the love of two young stdents.

B. The song she is singing says about the love of two young stdents.

C. The song says about the love of two young stdents which she is singing.

D. The song says about the love of two young stdents that she is singing it.

1
25 tháng 6 2021

EXERCISE 1: CHOOSE THE BEST ANSWER:

1. That’s my friend,_______________ comes from Japan.

A. which B. who C. whom D. where.

2. The plants which______________ in the living room need a lot of water.

A. are B. be C. is D. was

3. She’s the woman_______________ sister looks after the baby for us.

A. who B. which C. that’s D. whose

4. That’s the doctor for________________ Cliff works.

A. that B. which C. whom D. whose

5. Marie,______________ I met at the party, called me last night.

A. that B. whom C. which D. whose

6. I remember Alice,______________ rode the bus to school with.

A. I B. whom I C. which I D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

A. where B. when C. which D. that

8. Tell me about the city ______________ you grew up.

A. that B. where C. which D. ø

9. Anna found the book that ________________ wanted at the bookshop.

A. ø B. where C. she D. which

10. Please remember to take back to the library all the books ________ are due this week.

A. ø B. that C. when D. they

11. He likes the dress. Huong is wearing it

A. He likes the dress which Huong is wearing it

B. He likes the dress Huong is wearing it

C. He likes the dress who Huong is wearing

D. He likes the dress Huong is wearing

12. Most of the classmates couldn't come. He invited them to the birthday party

A. Most of the classmates he invited to the birthday party couldn't come.

B. Most of the classmates he was invited to the birthday party couldn't come.

C. Most of the classmates that he invited them to the birthday party couldn't come.

D. Most of the classmates which he invited to the birthday party couldn't come.

13. What was the name of the man? You met and talked to him this morning.

A. What was the name of the man who you met and talked to him this morning?

B. What was the name of the man you met and talked to this morning?

C. What was the name of the man you met and talked to whom this morning?

D. What was the name of the man whose you met and talked to this morning?

14. The church is over 500 years old. Our class visited it last summer.

A. The church which our class visited it last summer is over 500 years old.

B. The church that our class visited it last summer is over 500 years old.

C. The church which our class visited last summer is over 500 years old.

D. The church our class visit last summer is over 500 years old.

15. The song says about the love of two young stdents. She is singing the song.

A. The song which she is singing it says about the love of two young stdents.

B. The song she is singing says about the love of two young stdents.

C. The song says about the love of two young stdents which she is singing.

D. The song says about the love of two young stdents that she is singing it.

25 tháng 6 2021

vâng để e chia ra ạ

1. That’s my friend,_______________ comes from Japan.     A. which                           B. who                        C. whom                    D. where.2. The plants which______________ in the living room need a lot of water.     A. are                                B. be                           C. is                            D. was3. She’s the woman_______________ sister looks after the baby for us.     A. who                              B. which                    C. that’s...
Đọc tiếp

1. That’s my friend,_______________ comes from Japan.

     A. which                           B. who                        C. whom                    D. where.

2. The plants which______________ in the living room need a lot of water.

     A. are                                B. be                           C. is                            D. was

3. She’s the woman_______________ sister looks after the baby for us.

     A. who                              B. which                    C. that’s                     D. whose

4. That’s the doctor for________________ Cliff works.

     A. that                               B. which                    C. whom                    D. whose

5. Marie,______________ I met at the party, called me last night.

     A. that                               B. whom                    C. which                    D. whose

6. I remember Alice,______________ rode the bus to school with.

     A. I                                    B. whom I                  C. which I                  D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

     A. where                           B. when                      C. which                    D. that

8. Tell me about the city ______________ you grew up.

     A. that                               B. where                    C. which                    D. ø

9. Anna found the book that ________________ wanted at the bookshop.

     A. ø                                   B. where                    C. she             D. which

10. Please remember to take back to the library all the books ________ are due this week.

     A. ø                                   B. that                         C. when                      D. they

11. He likes the dress. Huong is wearing it

    A. He likes the dress which Huong is wearing it                                                                            

    B. He likes the dress Huong is wearing it

    C. He likes the dress who Huong is wearing   

    D. He likes the dress Huong is wearing

12. Most of the classmates couldn't come. He invited them to the birthday party

    A. Most of the classmates he invited to the birthday party couldn't come.

    B. Most of the classmates he was invited to the birthday party couldn't come.

    C. Most of the classmates that he invited them to the birthday party couldn't come.

    D. Most of the classmates which he invited to the birthday party couldn't come.

13. What was the name of the man? You met and talked to him this morning.

    A. What was the name of the man who you met and talked to him this morning?

    B. What was the name of the man you met and talked to this morning?

    C. What was the name of the man you met and talked to whom this morning?

    D. What was the name of the man whose you met and talked to this morning?

14. The church is over 500 years old. Our class visited it last summer.

    A. The church which our class visited it last summer is over 500 years old.

    B. The church that our class visited it last summer is over 500 years old.

    C. The church which our class visited last summer is over 500 years old.

    D. The church our class visit last summer is over 500 years old.

15. The song says about the love of two young stdents. She is singing the song.

    A. The song which she is singing it says about the love of two young stdents.

    B. The song she is singing says about the love of two young stdents.

    C. The song says about the love of two young stdents which she is singing.

    D. The song says about the love of two young stdents that she is singing it.

1
14 tháng 3 2022

1. That’s my friend,_______________ comes from Japan.

     A. which                           B. who                        C. whom                    D. where.

2. The plants which______________ in the living room need a lot of water.

     A. are                                B. be                           C. is                            D. was

3. She’s the woman_______________ sister looks after the baby for us.

     A. who                              B. which                    C. that’s                     D. whose

4. That’s the doctor for________________ Cliff works.

     A. that                               B. which                    C. whom                    D. whose

5. Marie,______________ I met at the party, called me last night.

     A. that                               B. whom                    C. which                    D. whose

6. I remember Alice,______________ rode the bus to school with.

     A. I                                    B. whom I                  C. which I                  D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

     A. where                           B. when                      C. which                    D. that

8. Tell me about the city ______________ you grew up.

     A. that                               B. where                    C. which                    D. ø

9. Anna found the book that ________________ wanted at the bookshop.

     A. ø                                   B. where                    C. she             D. which

10. Please remember to take back to the library all the books ________ are due this week.

     A. ø                                   B. that                         C. when                      D. they

11. He likes the dress. Huong is wearing it

    A. He likes the dress which Huong is wearing it                                                                            

    B. He likes the dress Huong is wearing it

    C. He likes the dress who Huong is wearing   

    D. He likes the dress Huong is wearing

12. Most of the classmates couldn't come. He invited them to the birthday party

    A. Most of the classmates he invited to the birthday party couldn't come.

    B. Most of the classmates he was invited to the birthday party couldn't come.

    C. Most of the classmates that he invited them to the birthday party couldn't come.

    D. Most of the classmates which he invited to the birthday party couldn't come.

13. What was the name of the man? You met and talked to him this morning.

    A. What was the name of the man who you met and talked to him this morning?

    B. What was the name of the man you met and talked to this morning?

    C. What was the name of the man you met and talked to whom this morning?

    D. What was the name of the man whose you met and talked to this morning?

14. The church is over 500 years old. Our class visited it last summer.

    A. The church which our class visited it last summer is over 500 years old.

    B. The church that our class visited it last summer is over 500 years old.

    C. The church which our class visited last summer is over 500 years old.

    D. The church our class visit last summer is over 500 years old.

15. The song says about the love of two young stdents. She is singing the song.

    A. The song which she is singing it says about the love of two young stdents.

    B. The song she is singing says about the love of two young stdents.

    C. The song says about the love of two young stdents which she is singing.

    D. The song says about the love of two young stdents that she is singing it.

 nhiều câu tớ làm ko đúng đâu nhé

cậu kiểm tra hộ tớ nhé vì tớ vẫn chưa học dạng này

14 tháng 5 2018

Đáp án: A

Chủ ngữ số nhiều nên toboe là “are”

CHOOSE THE BEST ANSWER:1. That’s my friend,_______________ comes from Japan.     A. which                             B. who                 C. whom              D. where.2. The plants which______________ in the living room need a lot of water.     A. are                        B. be                     C. is                      D. was3. She’s the woman_______________ sister looks after the baby for us.     A. who                      B. which               C. that’s                D. whose4....
Đọc tiếp

CHOOSE THE BEST ANSWER:

1. That’s my friend,_______________ comes from Japan.

     A. which                             B. who                 C. whom              D. where.

2. The plants which______________ in the living room need a lot of water.

     A. are                        B. be                     C. is                      D. was

3. She’s the woman_______________ sister looks after the baby for us.

     A. who                      B. which               C. that’s                D. whose

4. That’s the doctor for________________ Cliff works.

     A. that                       B. which               C. whom              D. whose

5. Marie,______________ I met at the party, called me last night.

     A. that                       B. whom              C. which               D. whose

6. I remember Alice,______________ rode the bus to school with.

     A. I                           B. whom I            C. which I             D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

     A. where                             B. when                C. which               D. that

8. Tell me about the city ______________ you grew up.

     A. that                       B. where               C. which               D. ø

9. Anna found the book that ________________ wanted at the bookshop.

     A. ø                           B. where               C. she                   D. which

10. Please remember to take back to the library all the books ________ are due this week.

     A. ø                           B. that                   C. when                D. they

11. He likes the dress. Huong is wearing it

   A. He likes the dress which Huong is wearing it                                                      

    B. He likes the dress Huong is wearing it

   C. He likes the dress who Huong is wearing                                                            

    D. He likes the dress Huong is wearing

12. Most of the classmates couldn't come. He invited them to the birthday party

   A. Most of the classmates he invited to the birthday party couldn't come.

   B. Most of the classmates he was invited to the birthday party couldn't come.

   C. Most of the classmates that he invited them to the birthday party couldn't come.

   D. Most of the classmates which he invited to the birthday party couldn't come.

13. What was the name of the man? You met and talked to him this morning.

   A. What was the name of the man who you met and talked to him this morning?

   B. What was the name of the man you met and talked to this morning?

   C. What was the name of the man you met and talked to whom this morning?

   D. What was the name of the man whose you met and talked to this morning?

14. The church is over 500 years old. Our class visited it last summer.

   A. The church which our class visited it last summer is over 500 years old.

   B. The church that our class visited it last summer is over 500 years old.

   C. The church which our class visited last summer is over 500 years old.

   D. The church our class visit last summer is over 500 years old.

15. The song says about the love of two young stdents. She is singing the song.

   A. The song which she is singing it says about the love of two young stdents.

   B. The song she is singing says about the love of two young stdents.

   C. The song says about the love of two young stdents which she is singing.

   D. The song says about the love of two young stdents that she is singing it.

 

 

 

 

 

 

 

1
29 tháng 8 2021

1b
2a
3d
4a
5b
6b
7b
8b
9c
10a
11a
12a
13b
14c
15b

Ex 1 : Choose the best answer 1 , That's my friend , ..........................comes from japan . A Which B who C Whom D Where 2 . The plants which .................................in the living room need a lot of water A are B be C is D was 3 , she 's the woman ..........................sister looks after the baby for us . A Who B Which C that's D Whose 4 , That's the doctor for ..................................cliff works. A that B which C whom D Whose 5 , Marie ,...
Đọc tiếp

Ex 1 : Choose the best answer

1 , That's my friend , ..........................comes from japan .

A Which B who C Whom D Where

2 . The plants which .................................in the living room need a lot of water

A are B be C is D was

3 , she 's the woman ..........................sister looks after the baby for us .

A Who B Which C that's D Whose

4 , That's the doctor for ..................................cliff works.

A that B which C whom D Whose

5 , Marie , .........................I met at the party , called me last night

A that B whom C which D whose

6 , I remember Alice , .....................................rode the bus to school with .

A I B Whom I C Which I D Who

7 , I used to enjoy the summer , ......................we had a big family picnic .

A where B when C which D that

8 , Tell me about the city......................you grew up .

A that B where C Which D Who

9 . ANNa found the book that ...............................wanted at the bookshop

A Who B Where C she D which

10 Please remember to take back to the library all the books .........................are due this week

A Who B that C when D they

0
CHOOSE THE BEST ANSWER: 1. That’s my friend,_______________ comes from Japan. A. which B. who C. whom D. where. 2. The plants which______________ in the living room need a lot of water. A. are B. be C. is D. was 3. She’s the woman_______________ sister looks after the baby for us. A. who B. which C. that’s D. whose 4. That’s the doctor for________________ Cliff works. A. that B. which C. whom D. whose 5. Marie,______________ I met at the party, called me last night. A. that B....
Đọc tiếp

CHOOSE THE BEST ANSWER:

1. That’s my friend,_______________ comes from Japan.

A. which B. who C. whom D. where.

2. The plants which______________ in the living room need a lot of water.

A. are B. be C. is D. was

3. She’s the woman_______________ sister looks after the baby for us.

A. who B. which C. that’s D. whose

4. That’s the doctor for________________ Cliff works.

A. that B. which C. whom D. whose

5. Marie,______________ I met at the party, called me last night.

A. that B. whom C. which D. whose

6. I remember Alice,______________ rode the bus to school with.

A. I B. whom I C. which I D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

A. where B. when C. which D. that

8. Tell me about the city ______________ you grew up.

A. that B. where C. which D. ø

9. Anna found the book that ________________ wanted at the bookshop.

A. ø B. where C. she D. which

10. Please remember to take back to the library all the books ________ are due this week.

A. ø B. that C. when D. they

2
12 tháng 9 2017

CHOOSE THE BEST ANSWER:

1. That’s my friend,_______________ comes from Japan.

A. which B. who C. whom D. where.

2. The plants which______________ in the living room need a lot of water.

A. are B. be C. is D. was

3. She’s the woman_______________ sister looks after the baby for us.

A. who B. which C. that’s D. whose

4. That’s the doctor for________________ Cliff works.

A. that B. which C. whom D. whose

5. Marie,______________ I met at the party, called me last night.

A. that B. whom C. which D. whose

6. I remember Alice,______________ rode the bus to school with.

A. I B. whom I C. which I D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

A. where B. when C. which D. that

8. Tell me about the city ______________ you grew up.

A. that B. where C. which D. ø

9. Anna found the book that ________________ wanted at the bookshop.

A. ø B. where C. she D. which

10. Please remember to take back to the library all the books ________ are due this week.

A. ø B. that C. when D. they

27 tháng 5 2018

CHOOSE THE BEST ANSWER:

1. That’s my friend,_______________ comes from Japan.

A. which B. who C. whom D. where.

2. The plants which______________ in the living room need a lot of water.

A. are B. be C. is D. was

3. She’s the woman_______________ sister looks after the baby for us.

A. who B. which C. that’s D. whose

4. That’s the doctor for________________ Cliff works.

A. that B. which C. whom D. whose

5. Marie,______________ I met at the party, called me last night.

A. that B. whom C. which D. whose

6. I remember Alice,______________ rode the bus to school with.

A. I B. whom I C. which I D. who

7. I used to enjoy the summer, ______________ we had a big family picnic.

A. where B. when C. which D. that

8. Tell me about the city ______________ you grew up.

A. that B. where C. which D. ø

9. Anna found the book that ________________ wanted at the bookshop.

A. ø B. where C. she D. which

10. Please remember to take back to the library all the books ________ are due this week.

A. ø B. that C. when D. they

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed....
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42.

Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed. Although bioluminescence is a relatively complicated process, it can be reduced to simple terms. Living light occurs when luciferin and oxygen combine in the presence of luciferase. In a few cases, fireflies the most common, an additional compound called ATP is required.

The earliest recorded experiments with bioluminescence in the late 1800s are attributed to Raphael Dubois, who extracted a luminous fluid from a clam, observing that it continued to glow in the test tube for several minutes. He named the substance luciferin, which means “the bearer of life”. In further research, Dubois discovered that several chemicals were required for bioluminescence to occur. In his notes, it was recorded that a second important substance, which he called luciferase, was always present. In later study of small, luminous sea creatures, Newton Harley concluded that luciferin was composed of carbon, hydrogen, and oxygen, which are the building blocks of all living cells. He also proved that there are a variety of luciferin and luciferase, specific to the plants and animals that produce them.

Much remains unknown, but many scientists who are studying bioluminescence now believe that the origin of the phenomenon may be traced to a time when there was no oxygen in the Earth’s atmosphere. When oxygen was gradually introduced to the atmosphere, it was actually poisonous to life forms, plants and animals produced light to use up the oxygen in a gradual but necessary adaptation. It is speculated that millions of years ago, all life may have produced light to survive. As the millennia passed, life forms on Earth became tolerant of, and finally dependent on oxygen, and the adaptation that produced bioluminescence was no longer necessary, but some primitive plants and animals continued to use the light for new functions such as mating or attracting prey.

Question 36: Which of the following is the main topic of the passage?

A. Cold light

B. Luciferase

C. Primitive plants and animals

D. Earth’s atmosphere

1
22 tháng 2 2019

Đáp án A

Dịch nghĩa: Chủ đề chính của bài viết là gì?

A. Ánh sáng lạnh

B. Luciferase

C. Thực vật và động vật nguyên thủy

D. Khi hậu trên trái đất

Giải thích: Ta thấy đoạn văn chủ yếu nói về bioluminescence (sự phát quang sinh học) hay còn gọi là cold light (ánh sáng lạnh)

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed....
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42.

Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed. Although bioluminescence is a relatively complicated process, it can be reduced to simple terms. Living light occurs when luciferin and oxygen combine in the presence of luciferase. In a few cases, fireflies the most common, an additional compound called ATP is required.

The earliest recorded experiments with bioluminescence in the late 1800s are attributed to Raphael Dubois, who extracted a luminous fluid from a clam, observing that it continued to glow in the test tube for several minutes. He named the substance luciferin, which means “the bearer of life”. In further research, Dubois discovered that several chemicals were required for bioluminescence to occur. In his notes, it was recorded that a second important substance, which he called luciferase, was always present. In later study of small, luminous sea creatures, Newton Harley concluded that luciferin was composed of carbon, hydrogen, and oxygen, which are the building blocks of all living cells. He also proved that there are a variety of luciferin and luciferase, specific to the plants and animals that produce them.

Much remains unknown, but many scientists who are studying bioluminescence now believe that the origin of the phenomenon may be traced to a time when there was no oxygen in the Earth’s atmosphere. When oxygen was gradually introduced to the atmosphere, it was actually poisonous to life forms, plants and animals produced light to use up the oxygen in a gradual but necessary adaptation. It is speculated that millions of years ago, all life may have produced light to survive. As the millennia passed, life forms on Earth became tolerant of, and finally dependent on oxygen, and the adaptation that produced bioluminescence was no longer necessary, but some primitive plants and animals continued to use the light for new functions such as mating or attracting prey.

Question 37: According to the author, why has bioluminescence continued in modern plants and animals?

A. For survival

B. For attracting prey

C. For producing heat

D. For burning excess oxygen

1
26 tháng 8 2018

Đáp án B

Dịch nghĩa: Theo tác giả, tại sao sự phát quang sinh học lại tiếp diễn đối với thực và động vật hiện đại?

A. Để sinh tồn

B. Để hấp dẫn con mồi

C. Để sản sinh nhiệt

D. Để đốt cháy oxy thừa

Giải thích: Thông tin nằm ở “. . .but some primitive plants and animals continued to use the light for new functions such as mating or attracting prey” - “nhưng một số loài động thực vật nguyên thủy vẫn tiếp tục sử dụng ánh sáng với những chức năng mới như tìm bạn đời hay hấp dẫn con mồi.”

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42. Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed....
Đọc tiếp

Read the following passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions from 36 to 42.

Light from a living plant or animal is called bioluminescence, or cold light, to distinguish it from incandescence or heat-generating light. Life forms could not produce incandescent light without being burned. Their light is produced in chemicals combining in such a way that little or no measurable heat is produced, and the life forms generating it are unharmed. Although bioluminescence is a relatively complicated process, it can be reduced to simple terms. Living light occurs when luciferin and oxygen combine in the presence of luciferase. In a few cases, fireflies the most common, an additional compound called ATP is required.

The earliest recorded experiments with bioluminescence in the late 1800s are attributed to Raphael Dubois, who extracted a luminous fluid from a clam, observing that it continued to glow in the test tube for several minutes. He named the substance luciferin, which means “the bearer of life”. In further research, Dubois discovered that several chemicals were required for bioluminescence to occur. In his notes, it was recorded that a second important substance, which he called luciferase, was always present. In later study of small, luminous sea creatures, Newton Harley concluded that luciferin was composed of carbon, hydrogen, and oxygen, which are the building blocks of all living cells. He also proved that there are a variety of luciferin and luciferase, specific to the plants and animals that produce them.

Much remains unknown, but many scientists who are studying bioluminescence now believe that the origin of the phenomenon may be traced to a time when there was no oxygen in the Earth’s atmosphere. When oxygen was gradually introduced to the atmosphere, it was actually poisonous to life forms, plants and animals produced light to use up the oxygen in a gradual but necessary adaptation. It is speculated that millions of years ago, all life may have produced light to survive. As the millennia passed, life forms on Earth became tolerant of, and finally dependent on oxygen, and the adaptation that produced bioluminescence was no longer necessary, but some primitive plants and animals continued to use the light for new functions such as mating or attracting prey.

Question 40: Where in the passage does the author explain how living light occurs?

A. Line 3-4

B. Line 5-7

C. Line 8-l0

D. Line 10-12

1
21 tháng 2 2018

Đáp án B

Dịch nghĩa: Ở đâu trong đoạn văn tác giả giải thích ánh sáng tự nhiên tồn tại như thế nào?

A. Dòng 3-4

B. Dòng 5-7

C. Dòng 8-10

D. Dòng 10-12

Giải thích: Thông tin nằm ở dòng 5-7 đoạn văn: “Living light occurs when luciferin and oxygen combine in the presence of luciferase. In a few cases, fireflies the most common, an additional compound called ATP is required” - “Ánh sáng sống diễn ra khi luciferin và oxy kết hợp với sự có mặt của luciferase. Trong một số ít trường hợp, phổ biến nhất đối với đom đóm, cần một chất hóa học khác là ATP.”

=> Có thể thấy trong 2 câu này tác giả đã giải thích quá trình hình thành của ánh sáng sống.