UNLESS (TRỪ KHI) = IF ..... NOT (NẾU KHÔNG)
CÔNG DỤNG CÔNG THỨC CỦA
UNLESS
CÔNG THỨC CỦA
MỆNH ĐỀ IF (PHỤ)
- unless = if ... not
- unless chỉ dùng để thay thế mệnh đề phụ
trong câu điều kiện, mệnh đề chính không đổi.
1. Unless S + V1/s(es) ↔ If S + don’t / doesn’t +
Vo
2. Unless S + am, is, are ↔ If S + am, is, are + not
3. Unless S + V2/ ed ↔ If S + didn’t + Vo
4. Unless S + were ↔ If S + weren’t
5. Unless S + had V3/ed ↔ If S + hadn’t V3/ed
6. Unless S + had been ↔ If S + hadn’t been
Examples :
1. Unless you stay at your bed, you will be punished.
 If you don’t stay at your bed, you will be punished.
2. Unless she drinks water, she will feel thirsty.
 If she doesn’t drink beer, she will feel thirsty.
3. Unless they were absent now, they would meet the head master.
 If they weren’t absent now, they would meet the head master.
4. Unless he cleaned up the car now, his boss could ask him to do this.
 If he didn’t clean up the car now, his boss could ask him to do this.
5. Unless you had stayed at home yesterday, you wouldn’t have enjoyed a delicious meal.
 If you hadn’t stayed at home yesterday, you wouldn’t have enjoyed a delicious meal.
6. Unless he had been busy last night, he could have met his friends.
 If he hadn’t been busy last night, he could have met his friends.
Rewrite the statements by using the conditional sentences:
1. You can’t run fast unless you try your best.
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17. Her car wouldn’t have been broken yesterday unless she had driven fast.
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18. Hoa wrote to her parents. She wanted to greet them.
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19. Unless people knew you, they wouldn’t give you some precious information.
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20. Because these projects were out of date, the manager looked uncomfortable.
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21. Unless the young girl stops smoking, she won’t be healthy.
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22. I don’t like cats because cats are fury.
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23. Unless ten years ago they had lived in USA, they couldn’t have been the citizens in this country.
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24. Tom didn’t join the camping. I couldn’t persuade him to go with us.
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25. People can’t swim unless they study how to swim.
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26. Anne doesn’t attend the party because she wants to be alone.
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27. This department couldn’t be destroyed unless it built carefully.
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28. Susan agreed to go swimming because she liked water.
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29. Yesterday, I could have been injured unless I had seen a big container in the street.
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30. Sports make people healthy, so they do exercise every morning.
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31. Unless you were me, you couldn’t understand me.
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