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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example,...
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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.

Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example, insects disappear during the cold months, prompting insect-dependent birds to fly south to warm areas where insects breed. No similar consensus has emerged, however, about how birds are able to navigate. Despite many recent experiments, bird experts still do not know how birds arrive at the same destinations every year and then find their way back home in the spring.

Some have suggested that birds find their way by following landmarks, such as rivers and mountain ranges. Experiments have confirmed that some species do follow such topographic features. But that method cannot explain how some birds travel at night. Other studies show that some nocturnal birds navigate by the stars. But that explanation cannot explain daytime migration or travel when the skies are cloudy.

The most popular explanation currently is that birds are guided by Earth’s magnetic poles. The mechanism by which that works has not yet been proved. One theory points to the fact that some birds’ contain magnetite, a naturally occurring magnetic compound consisting of iron oxide. Magnetite has been found in many animals, including birds. With magnets embedded in their brains, birds would be able to sense the magnetic fields of the North and South Poles.

A recent experiment with homing pigeons provided some evidence that magnetite does play a crucial role in migration. Homing pigeons are known to have the ability to return to their homes after being taken hundreds of miles away. Researchers found that they could train homing pigeons to recognize changes in a magnetic field. When a surrounding magnetic field was normal, the birds would gather at one end of a cage. But when the field’s polarity was altered, they hopped to the other end, suggesting that they were directing and responding to changes in the magnetic field.

Another theory has been offered to explain this sensitivity to magnetic poles, a theory that draws upon quantum mechanics, which is the study of how particles move inside an atom. It relies on the fact that electrons come in pairs that orbits the nucleus of an atom. The two electrons spin in opposite directions, creating two magnets that neutralize each other. But when molecules split and react with other molecules to form compounds, the electrons pairs may no longer spin in opposite directions. Instead,  they may repel each other, as when two north ends of magnets are pressed together. The electrons struggle to change direction in order to achieve a stable state in which the two electrons again neutralize each other, giving off no magnetic field. 

Which of the following can be inferred about an electron pair in two north ends of magnets?

A. The two electrons spin in opposite directions

B. One electron will move to the south end

C. One electron will be captured by the nucleus

D. The two electrons spin in the same direction  

1
4 tháng 3 2019

Đáp án : D

They may repel each other, as when two north ends of magnets are pressed together

 Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example,...
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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.

Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example, insects disappear during the cold months, prompting insect-dependent birds to fly south to warm areas where insects breed. No similar consensus has emerged, however, about how birds are able to navigate. Despite many recent experiments, bird experts still do not know how birds arrive at the same destinations every year and then find their way back home in the spring.

Some have suggested that birds find their way by following landmarks, such as rivers and mountain ranges. Experiments have confirmed that some species do follow such topographic features. But that method cannot explain how some birds travel at night. Other studies show that some nocturnal birds navigate by the stars. But that explanation cannot explain daytime migration or travel when the skies are cloudy.

The most popular explanation currently is that birds are guided by Earth’s magnetic poles. The mechanism by which that works has not yet been proved. One theory points to the fact that some birds’ contain magnetite, a naturally occurring magnetic compound consisting of iron oxide. Magnetite has been found in many animals, including birds. With magnets embedded in their brains, birds would be able to sense the magnetic fields of the North and South Poles.

A recent experiment with homing pigeons provided some evidence that magnetite does play a crucial role in migration. Homing pigeons are known to have the ability to return to their homes after being taken hundreds of miles away. Researchers found that they could train homing pigeons to recognize changes in a magnetic field. When a surrounding magnetic field was normal, the birds would gather at one end of a cage. But when the field’s polarity was altered, they hopped to the other end, suggesting that they were directing and responding to changes in the magnetic field.

Another theory has been offered to explain this sensitivity to magnetic poles, a theory that draws upon quantum mechanics, which is the study of how particles move inside an atom. It relies on the fact that electrons come in pairs that orbits the nucleus of an atom. The two electrons spin in opposite directions, creating two magnets that neutralize each other. But when molecules split and react with other molecules to form compounds, the electrons pairs may no longer spin in opposite directions. Instead,  they may repel each other, as when two north ends of magnets are pressed together. The electrons struggle to change direction in order to achieve a stable state in which the two electrons again neutralize each other, giving off no magnetic field. 

According to paragraph 3, birds can detect the magnetic fields of the North and South poles because

 

A. they sense the motion of electron pairs

B. they can locate the poles by following landmarks

C. they ingest metal particles that are attracted by the poles

D. they have magnetite in their brains

1
27 tháng 4 2017

Đáp án : D

D.With magnets embeded in their brains, birds would be able to sense the magnetic fields of the North and South Poles

Read the passage and answer the questions below:Air pollution is a serious problem in many cities. Wastes of motor vehicles, factories and other sources create so much air pollution that it may hang in the air like dirty fog. Air pollution threatens the health of the people who live in cities. City wastes cause water pollution when they are poured into the waterways. These wastes kill fish and make some areas unfit for swimming. In addition, many large cities have difficulties in disposing of...
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Read the passage and answer the questions below:

Air pollution is a serious problem in many cities. Wastes of motor vehicles, factories and other sources create so much air pollution that it may hang in the air like dirty fog. Air pollution threatens the health of the people who live in cities. City wastes cause water pollution when they are poured into the waterways. These wastes kill fish and make some areas unfit for swimming. In addition, many large cities have difficulties in disposing of their garbage. The amount of garbage grows each year, but places to put it are quickly filling up. Citizens, governments, industries, scientists, and business people must work together in different ways to gradually reduce pollution. For example, most cities have introduced recycling programmes.

1. What can be created from wastes of motor vehicles, factories and other sources ?

.......…………………………………………………………………………………………………………….

2. Can air pollution influence badly on people who live around it ?

.......…………………………………………………………………………………………………………….

3. When do city wastes pollute water ?

.......…………………………………………………………………………………………………………….

4. Why is it difficult to have places for putting garbage ?

.......…………………………………………………………………………………………………………….

5. What must all people do to reduce pollution ?

....………………………………………………………………………………………………………

1
21 tháng 2 2022

1. Wastes of motor vehicles, factories and other sources create so much air pollution that it may hang in the air like dirty fog.

2. Yes, air pollution threatens the health of the people.

3. When they are poured into the waterways.

4. Because the amount of garbage grows each year, but places to put it are quickly filling up.

5. People must work together in different ways to gradually reduce pollution. For example, most cities have introduced recycling programmes.

Read the following passage: Recycling is important in improving the environment. Below are some helpful tips about recycling in and around the home. 1. Find ways of recycling different materials Many materials can be recycled, such as paper, plastic, metal and glass. Other items such as furniture, electronic equipment, building material and vehicles can also be recycled. 2. Buy products that can be recycled When shopping at the supermarket, buy products that can be recycled easily such as...
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Read the following passage:

Recycling is important in improving the environment. Below are some helpful tips about recycling in and around the home.

1. Find ways of recycling different materials

Many materials can be recycled, such as paper, plastic, metal and glass. Other items such as furniture, electronic equipment, building material and vehicles can also be recycled.

2. Buy products that can be recycled

When shopping at the supermarket, buy products that can be recycled easily such as glass jars and tin cans.

3. Recycling bins

Make sure you have a recycling bin in your home. Keep it in an obvious place so you won’t forget to use it.

Find the word in the passage having the similar meaning with the explanation:

1. the pieces of information, especially about how to do something ____________

2. a large shopwhich sells most types of food and other goodsneeded in the home ____________

True or false?

3. Plastic cannot be recycled. ____________

4. When shopping, it is a good idea to buy things from glass. ____________

5. It is better to put the recycling bins in obvious places. ____________

3
27 tháng 4 2017

Read the following passage:

Recycling is important in improving the environment. Below are some helpful tips about recycling in and around the home.

1. Find ways of recycling different materials

Many materials can be recycled, such as paper, plastic, metal and glass. Other items such as furniture, electronic equipment, building material and vehicles can also be recycled.

2. Buy products that can be recycled

When shopping at the supermarket, buy products that can be recycled easily such as glass jars and tin cans.

3. Recycling bins

Make sure you have a recycling bin in your home. Keep it in an obvious place so you won’t forget to use it.

True or false?

3. Plastic cannot be recycled. _FALSE_

4. When shopping, it is a good idea to buy things from glass. _TRUE_

5. It is better to put the recycling bins in obvious places. _TRUE_

28 tháng 4 2017

Read the following passage:

Recycling is important in improving the environment. Below are some helpful tips about recycling in and around the home.

1. Find ways of recycling different materials

Many materials can be recycled, such as paper, plastic, metal and glass. Other items such as furniture, electronic equipment, building material and vehicles can also be recycled.

2. Buy products that can be recycled

When shopping at the supermarket, buy products that can be recycled easily such as glass jars and tin cans.

3. Recycling bins

Make sure you have a recycling bin in your home. Keep it in an obvious place so you won’t forget to use it.

Find the word in the passage having the similar meaning with the explanation:

True or false?

3. Plastic cannot be recycled. False

4. When shopping, it is a good idea to buy things from glass. True

5. It is better to put the recycling bins in obvious places. True

*Put ONE suitable word into each space Our classes take place for three hours every morning from Monday (1) Friday. The maximum class size twelve (2) the average is ten. We use moderns of (3) and learning, and the school has a language laboratory, a video camera and recorders. However, you will only be successful in improving (4) English if you work hard and (5) speaking English much, as you can. You will take a short (6) in English as soon as you arive. In this way, we can put you in a (7) at...
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*Put ONE suitable word into each space

Our classes take place for three hours every morning from Monday (1) Friday. The maximum class size twelve (2) the average is ten. We use moderns of (3) and learning, and the school has a language laboratory, a video camera and recorders. However, you will only be successful in improving (4) English if you work hard and (5) speaking English much, as you can. You will take a short (6) in English as soon as you arive. In this way, we can put you in a (7) at the most suitable level. There are two classes at the Elementary level, one is for complete beginners the other is for students who know only a little English. In both classes you will practise simple conversations. In the class (8) the intermediate level you will have a lot of practice in communication in real-life situation because we help you to use the English you have previously (9) in your own country, you will also have the chance to improve your (10) of English grammar and to build up your vocabulary...

1
26 tháng 9 2018

Our classes take place for three hours every morning from Monday (1) to Friday. The maximum class size twelve (2)and the average is ten. We use moderns of (3)teaching and learning, and the school has a language laboratory, a video camera and recorders. However, you will only be successful in improving (4)your English if you work hard and (5) practise speaking English much, as you can. You will take a short (6)test in English as soon as you arive. In this way, we can put you in a (7)class at the most suitable level.

There are two classes at the Elementary level, one is for complete beginners the other is for students who know only a little English. In both classes you will practise simple conversations. In the class (8)for the intermediate level you will have a lot of practice in communication in real-life situation because we help you to use the English you have previously (9) in your own country, you will also have the chance to improve your (10)knowledge of English grammar and to build up your vocabulary...

Fill each of the numbered blanks in the following passages. Use only ONE word for each space Many people dream of (1)..... in a foreign country. It can be an amazing experience (2)....... those who have the courage to leave their family and friends and settle down in a new place. (3)......., there's one potential problem you should be aware of: culture shock. Culture shock is the feeling we get from living in a place that is so different to where we grew up that we are not sure (4)....... to...
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Fill each of the numbered blanks in the following passages. Use only ONE word for each space

Many people dream of (1)..... in a foreign country. It can be an amazing experience (2)....... those who have the courage to leave their family and friends and settle down in a new place. (3)......., there's one potential problem you should be aware of: culture shock. Culture shock is the feeling we get from living in a place that is so different to where we grew up that we are not sure (4)....... to deal with it. Societies are organized in many different ways, and we can often (5)...... taken aback by some of the things we find in foreign countries. Customs and traditions can be very different and that can sometimes make (6)...... difficult to get on with local people and to make friends. They migt not approve of things you do or might object to things you say. You might even be banned from doing things in another country that are perfectly legal in your own. (7)...... you were to move to a country such as Singapore, say, you might find some of the laws very (8)..... There, people can be forced to pay a large fine just for dropping litter. Eventually, (9)....., most people who live abroad fall in love with their adopted country and learn to accept its differences. It does take real courage to make such a big change (10)..... your life, but many people agree that it is worth it in the end

1
2 tháng 6 2019

Fill each of the numbered blanks in the following passages. Use only ONE word for each space

Many people dream of (1)..living... in a foreign country. It can be an amazing experience (2)...for.... those who have the courage to leave their family and friends and settle down in a new place. (3)....however..., there's one potential problem you should be aware of: culture shock. Culture shock is the feeling we get from living in a place that is so different to where we grew up that we are not sure (4)...how.... to deal with it. Societies are organized in many different ways, and we can often (5)...be... taken aback by some of the things we find in foreign countries. Customs and traditions can be very different and that can sometimes make (6).it..... difficult to get on with local people and to make friends. They migt not approve of things you do or might object to things you say. You might even be banned from doing things in another country that are perfectly legal in your own. (7)...if... you were to move to a country such as Singapore, say, you might find some of the laws very (8)...quickly.. There, people can be forced to pay a large fine just for dropping litter. Eventually, (9)..though..., most people who live abroad fall in love with their adopted country and learn to accept its differences. It does take real courage to make such a big change (10)...in.. your life, but many people agree that it is worth it in the end

I- Finish each of the following sentences in such a way that it means exactly the same as the sentence printed before it. (10points) 1. We live in the same sweet. We rarely see each other.  SPITEà ………………………………………………………………………………………..2. He is very good at speaking English.  SPEAKERà ………………………………………………………………………………………..3. This is the best computer I have ever used.  SUCHà ………………………………………………………………………………………..4. The girl is very intelligent.  HOWà ………………………………………………………………………………………!5. My father drives...
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I- Finish each of the following sentences in such a way that it means exactly the same as the sentence printed before it. (10points)

1. We live in the same sweet. We rarely see each other.  SPITE

à ………………………………………………………………………………………..

2. He is very good at speaking English.  SPEAKER

à ………………………………………………………………………………………..

3. This is the best computer I have ever used.  SUCH

à ………………………………………………………………………………………..

4. The girl is very intelligent.  HOW

à ………………………………………………………………………………………!

5. My father drives very carefully, and my brother does, too. SO

à ………………………………………………………………………………………..

0
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example,...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.

Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example, insects disappear during the cold months, prompting insect-dependent birds to fly south to warm areas where insects breed. No similar consensus has emerged, however, about how birds are able to navigate. Despite many recent experiments, bird experts still do not know how birds arrive at the same destinations every year and then find their way back home in the spring.

Some have suggested that birds find their way by following landmarks, such as rivers and mountain ranges. Experiments have confirmed that some species do follow such topographic features. But that method cannot explain how some birds travel at night. Other studies show that some nocturnal birds navigate by the stars. But that explanation cannot explain daytime migration or travel when the skies are cloudy.

The most popular explanation currently is that birds are guided by Earth’s magnetic poles. The mechanism by which that works has not yet been proved. One theory points to the fact that some birds’ contain magnetite, a naturally occurring magnetic compound consisting of iron oxide. Magnetite has been found in many animals, including birds. With magnets embedded in their brains, birds would be able to sense the magnetic fields of the North and South Poles.

A recent experiment with homing pigeons provided some evidence that magnetite does play a crucial role in migration. Homing pigeons are known to have the ability to return to their homes after being taken hundreds of miles away. Researchers found that they could train homing pigeons to recognize changes in a magnetic field. When a surrounding magnetic field was normal, the birds would gather at one end of a cage. But when the field’s polarity was altered, they hopped to the other end, suggesting that they were directing and responding to changes in the magnetic field.

Another theory has been offered to explain this sensitivity to magnetic poles, a theory that draws upon quantum mechanics, which is the study of how particles move inside an atom. It relies on the fact that electrons come in pairs that orbits the nucleus of an atom. The two electrons spin in opposite directions, creating two magnets that neutralize each other. But when molecules split and react with other molecules to form compounds, the electrons pairs may no longer spin in opposite directions. Instead,  they may repel each other, as when two north ends of magnets are pressed together. The electrons struggle to change direction in order to achieve a stable state in which the two electrons again neutralize each other, giving off no magnetic field. 

The word “altered” in the passage is closest in meaning to

A. reversed                    

B. cancelled          

C. strengthened              

D. detected

1
13 tháng 7 2019

Đáp án : A

A.Alter: thay đổi

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example,...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 44.

Bird migration is one of the most interesting yet least understood natural phenomena. Every fall birds from northern latitudes fly in groups to the warmer southern latitudes and then return north in the spring. Scientists agree on the main reasons for migration: to follow the food supply and to avoid harsh climate conditions. For example, insects disappear during the cold months, prompting insect-dependent birds to fly south to warm areas where insects breed. No similar consensus has emerged, however, about how birds are able to navigate. Despite many recent experiments, bird experts still do not know how birds arrive at the same destinations every year and then find their way back home in the spring.

Some have suggested that birds find their way by following landmarks, such as rivers and mountain ranges. Experiments have confirmed that some species do follow such topographic features. But that method cannot explain how some birds travel at night. Other studies show that some nocturnal birds navigate by the stars. But that explanation cannot explain daytime migration or travel when the skies are cloudy.

The most popular explanation currently is that birds are guided by Earth’s magnetic poles. The mechanism by which that works has not yet been proved. One theory points to the fact that some birds’ contain magnetite, a naturally occurring magnetic compound consisting of iron oxide. Magnetite has been found in many animals, including birds. With magnets embedded in their brains, birds would be able to sense the magnetic fields of the North and South Poles.

A recent experiment with homing pigeons provided some evidence that magnetite does play a crucial role in migration. Homing pigeons are known to have the ability to return to their homes after being taken hundreds of miles away. Researchers found that they could train homing pigeons to recognize changes in a magnetic field. When a surrounding magnetic field was normal, the birds would gather at one end of a cage. But when the field’s polarity was altered, they hopped to the other end, suggesting that they were directing and responding to changes in the magnetic field.

Another theory has been offered to explain this sensitivity to magnetic poles, a theory that draws upon quantum mechanics, which is the study of how particles move inside an atom. It relies on the fact that electrons come in pairs that orbits the nucleus of an atom. The two electrons spin in opposite directions, creating two magnets that neutralize each other. But when molecules split and react with other molecules to form compounds, the electrons pairs may no longer spin in opposite directions. Instead,  they may repel each other, as when two north ends of magnets are pressed together. The electrons struggle to change direction in order to achieve a stable state in which the two electrons again neutralize each other, giving off no magnetic field. 

The word “embedded” in the passage is closest in meaning to

A. implanted                  

B. attached           

C. attracted          

D. activated

1
13 tháng 4 2019

Đáp án : A

A.Embed = implant: ghi vào/ khắc sâu trong trí nhớ