Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
1. is watering
2. is going to rain
3. didn't send
4. to keep
16.Tom (not go) ...............hasn't gone............. out since he (fail) .......failed........... in his exam.
17.I (not wear) .........haven't worn................... that skirt since Mary’s birthday. 18.It started to rain while you (sleep) ..........were sleeping....................
19.He (cross) ..............was crossing................ the street when I (see) ...........saw........him yesterday.
20.He (leave) .........left..........home 2 weeks ago and we (not hear) ................haven't heard........from him since.
21.What........were..... you (do) ......doing............. at that time last week ? 22.Last Sunday, An (watch) ..........was watching..................... TV when Tom (come) ..........came.........here.
23.John (do) ...........has done................ his homework already.
24.Yesterday while I (water) ..........were watering.................the garden, it (begin) .............was begining...... to rain.
25.He (read) ...............has read.............. 53 pages so far
26..........Is...... he (write) ..........writing....... a novel at present ?
27.They (not speak)..............haven't spoken................... to each other since they quarreled.
28.Listen ! Somebody (knock) ...............is knocking..................... the door. 29.Please don’t say anything while I (learn) ...................were learning ................... my lesson.
30.Up to now, I (do) ...................have done .................. every exercise in this book
viết lại câu sao cho nghĩa không đổi
1. I do not buy it because I do not have enough money
--> If I had enough money , i would buy it
2. I am búy now, so I can not help you
--> If I weren't buying now , i could help you
3. There will be a shortage of water unless it rains
--> If it doesn't rain , there will be a shortage of water
4. John is fat because she eat many chips
--> If she didn't eat many chips , she wouldn't be fat
5. I will only help you if you promise to try harder
--> Unless you promise to try harder , i won't help you
6. If it does not rain soon, the srops will be lost
--> Unless it rains soon , the crops will be lost
7. I am very tired so I can not concentrate properly
--> If i weren't tired , i could concentrate properly
8.We do not have a garden , so we do not grow our own vegetables
--> If we had a garden , we would grow our own vegetables
9. He does not give you good advice because he is not your true friend
--> If he were your true friend , he would giv you good advice
10. We come late becavuse the rain is so havely
--> If the rain weren;t so heavy , we wouldn't come late
viết lại câu sao cho nghĩa không đổi
1. I do not buy it because I do not have enough money
--> If I had enough money, I would buy it.
2. I am búy now, so I can not help you
--> If I wasn't busy now, I could help you.
3. There will be a shortage of water unless it rains
--> If it didn't rain, there would be a shortage of water.
4. John is fat because she eat many chips
--> If she didn't eat many chips, she wouldn't be fat.
5. I will only help you if you promise to try harder
--> Unless you promise to try harder, I will not help you.
6. If it does not rain soon, the srops will be lost
--> Unless it rains soon, the srops will be lost.
7. I am very tired so I can not concentrate properly
--> If I wasn't very tired, I could concentrate properly.
8.We do not have a garden , so we do not grow our own vegetables
--> If we had a garden, we would grow our own vegetables.
9. He does not give you good advice because he is not your true friend
--> If he was your true friend, he would give you good advice.
10. We come late becavuse the rain is so havely
--> If the rain wasn't so heavy, we wouldn't come late.
One of the most urgent environmental problems in the world today is the shortage of clean water. Having clean drinking water is basic human right. But acid rain, industrial pollution and garbage have made many sources of water undrinkable. Lakes, reservoirs and even entire seas have become vast pools of poison. Lake Baikal in Russia is one of the largest lakes in the world. It contains a rich variety of animals and plants, including 1,300 rare species that do not exist anywhere else in the world. But they are being destroyed by the massive volumes of industrial effluent which pours into the lake everyday. Even where law existed, the government did not have the power to enforce them. Most industries simply ignore the regulations. The Mediterranean Sea occupies 1% of the world’s water surface. But it is the dumping ground for 50% of all marine pollution. Almost 16 countries regularly throw industrial wastes a few miles off shore.
Water is free to everyone. A few years ago people thought that the supply of clean water in the world was limitless. Today, many water supplies have been ruined by pollution and sewage. Clean water is now scarce, and we are at last beginning to respect this precious source. We should do something now.
1. According to the writer, one environmental problem in the world today is ________ .
A. acid rain B. industrial pollution.
C. safe water shortage. D. population explosion .
2. Many sources of water are not drinkable because of _______ .
A. acid rain. B. industrial pollution.
C. garbage D. all A, B, C, are correct
3. What is serious problem of Lake Baikal in Russia?
A. It contains a rich variety of animals and plants.
B. It is polluted by massive volumes of industrial wastes discharged into it .
C. It has 1,300 rare species that do not exist anywhere else in the world .
D. The government did not have the power to enforce laws and regulations.
4. How many countries throw industrial waste into the Mediterranean Sea regularly?
A. nearly 16 B. exactly 16.
C. exactly 15 D. less than 15.
5. What is the message to the reader?
A. We should take action to protect our water resources.
B. We should take all water resources into account.
C. We should limit the use of water resources.
D. We should encourage people to use safe water.
Chúc bạn học tốt 
I. Put the verb in brackets into the correct tenses:
1. If i see him, I (give).....will give....him a gift
2. If he (study).studies..hard, he can't pass the exam.
3. Rices plants (grow)...will grow...if there is enough rain
4. If she (not hurry)...doesn't hurry....., she may be late
5. If i tell you a secret,.......will...you (promise)...promise...not to tell it to anyone?
1. He told me to stay at home then.
2. He said that if it didn't rain the next day, the race could take place on time.
3. She said that she had come back there early the previous day.
4. They said they should eat more vegetables every day.
5. They said they would wait until he came back.
6. They said they kept talking about those animals they loved.
7. She said that she had broken the vase.
8. Hoa said that she would help her mum cook dinner that night.
9. Nam said that his best friend hadn't called him for one week.
10. Mr. Quang said to Trung that they had spoken to his parents the day before.
11. Mary said that she had just decided to register a dancing club to refresh herself.
12. Lan said that she and her close friend had had a quarrel the previous week, so she felt sad.
13. Tom said that he had already had breakfast, so he wasn't hungry.
14. She said to him that she wanted to go to that club with him but she was busy.
15. He told them that their supervisor would be there in five minutes.
a) Nam keeps forgetting his homework => Nam is ...always forgetting his homework
b) My mother gave me a very nice watch yesterday => I was ...given a very nice watch yesterday by my mother
c) We'd prefer you not to moke => We'd rather ...you didn't smoke
d) The water was so cold that the children couldn't swim in it => The water ...too cold for the children to swim in
e) To live on your salery must be hard => It...must be hard to live on your salery
f) It's interesting to read this book => this book...is interesting
g) A boy was injured in the accident , he is now in the hospital => The boy ...who was injured in the accident , is now in the hospital
a) Nam keeps forgetting his homework
=> Nam is always forgetting his homework.
b) My mother gave me a very nice watch yesterday
=> I was given a very nice watch by my mother yesterday.
c) We'd prefer you not to smoke
=> We'd rather you didn't smoke.
d) The water was so cold that the children couldn't swim in it
=> The water was too cold for the children to swim in.
e) To live on your salary must be hard
=> It must be hard to live on your salary.
g) A boy was injured in the accident , he is now in the hospital
=> The boy who was injured in the accident is now in the hospital.
bài tập về câu điều kiện loại 1,2,3
`1 if i ( have )......have....... time , i will write to him
2 if itt is coll , i ( need ) ..........will need..................a heavier coat 3. what are you going to do if you ( have) ...................have....... a holiday?
5 if I meet Helen , I ( give )............will give..............................her your message
6 if flowers don't get any water , they (die)..........will die...........................................
7 if I ( get ) ........get..................... a headache , i usually take some aspirins
8 i will go to the party unless it ( rain)............rains......................................
9 she will buy the car as long as it (not be).........isn't..................... too expensive
10 everything ( be ) ........is....................provided yo tell the truth
11 if he (come)..........comes.........., please tell him that i will be back in a few mintes
12 don't come if they (not call )..........don't call............you
13 if you (need )........need................., why don't you tell me?
14 suppose you (win)..........won...............a lot of money , what would you do ?
15 if i got up earlier, i (not be ).............wouldn't be...............late for work
16 if i didn't fell so tired , i (go ) .....would go..........out with you
17 if you ( not pass).....diđn't pass........the exam, would you take it again ?
18 if i ( not be ) .......hadn't been...........busy yesterday , i would have visited you
19 suppose they had offered her a job , do you think she (take )......would have taken..........it ?
20 if i (know)...........had known................that you were ill , i (go)............would ahve gone........to see you
21 i (see)........will see..........him if i (go)........go................to the party tonight
22 my dark (bark)...........will bark...............if it (hear)..........hears..............anything strong
23 what ......will...........we (do)........do...........if they (come)............come.........tomorrow?
24 if she hadn't been ill yesterday , she (go )......would have gone..........to work now
25 if i can go tomorrow , i (let).........will let......you know
bài tập về câu điều kiện loại 1,2,3
`1 if i ( have )...have.... time , i will write to him
2 if it is coll , i ( need ) ....will need......a heavier coat .
3. what are you going to do if you ( have) .......have..... a holiday?
5 if I meet Helen , I ( give )...........will give.............her your message
6 if flowers don't get any water , they (die).........will die................
7 if I ( get ) .....get..... a headache , i usually take some aspirins
8 i will go to the party unless it ( rain)..........rains.................
9 she will buy the car as long as it (not be)....isn’t...... too expensive
10 everything ( be ) ..........will be.....provided yo tell the truth
11 if he (come)....comes....., please tell him that i will be back in a few mintes
12 don't come if they (not call ).....don’t call........you
13 if you (need )........need........, why don't you tell me?
14 suppose you (win).......won......a lot of money , what would you do ?
15 if i got up earlier, i (not be ).......wouldn’t be....late for work
16 if i didn't fell so tired , i (go ) ....would go....out with you
17 if you ( not pass)...didn’t pass......the exam, would you take it again ?
18 if i ( not be ) ....had been...busy yesterday , i would have visited you
19 suppose they had offered her a job , do you think she (take )........would have taken......it ?
20 if i (know)..........knew........that you were ill , i (go).....would go........to see you
21 i (see).......will see.....him if i (go)......go.......to the party tonight
22 my dark (bark)...........will bark.......if it (hear).....hears....anything strong
23 what ........will ....we (do).....do.....if they (come).......come..tomorrow?
24 if she hadn't been ill yesterday , she (go )......would go....to work now
25 if i can go tomorrow , i (let)......will let...you know
1. It didn't rain yesterday. So I had to water the plants yesterday.
—> If it ..had rained... yesterday, I .wouldn't have watered..... the plants.
2. It didn't rain yesterday. So I am watering the plants now.
—>If it .had rained......... yesterday, I (water/ not) ..wouldn't water............ the plants now.
1. had rained / would n't have watered
2. had rained / wouldn't water