（4）否定句（Negatives）

肯定句	否定句
（1）I tell a lie.	I do not tell a lie.
（2）I have a book.	I have not a book. I do not have a book.（美）
（3）I am a student.	I am not a student.
（4）I can speak English.	I can not speak English.

例（1）表示凡無助動詞的肯定句變?yōu)榉穸ň鋾r，須補上助動詞 do，然后在 do 后加上 not。但用 never 時，則不需加 do。

例（2）和（3）表示 have 和 be 兩動詞，其否定句可不用助動詞，只將 not 放在它們之后即可。

have 用 do 來構(gòu)成否定句，系美國的用法。

例（4）表示凡有助動詞的肯定句變?yōu)榉穸ň鋾r，只在第一個助動詞之后加上 not 即可。

英文中只有十二個動詞或助動詞，not 可放在其后，茲舉出以供參考：have、be、do、shall、will、can、may、must、ought、need、dare、used。

但其中 do 用為動詞時，則與一般動詞同，須用 do 來構(gòu)成否定，如“Why don’t you do it？”。need 和 dare 亦然，如“I don’t need any more help now. ”，“I didn’t dare to go. ”。又，used not 之縮短形為 usen’t 或 usedn’t（d 不發(fā)音）。

注意：（1）用 never 來構(gòu)成否定句時，則不需用 do。如“I never tell a lie. ”neither...nor 之時亦同，如“I like neither this nor that. ”。

（2）一切命令句，不論何種動詞，概用 do not（don’t）來構(gòu)成否定句，如“Don’t be silly！”“Do not go！”等。

（3）have to（= must）的否定形為 do not have to，絕不可誤為 have not to。

（4）不定詞及分詞之否定形：將 not 放在前，如“to be or not to be”；“not knowing，I cannot cry. ”。

練習題（10）

A. 用 not 于適當?shù)牡胤剑兿铝芯渥訛榉穸ň洌?/p>

1. He has gone out of town.

2. They will be in class tomorrow.

3. I can meet you tonight.

4. I may be able to go with you.

5. We are going to the seashore on our vacation.

6. He will leave on the five o’clock train.

7. He is an engineer.

8. Mr. Smith has studied English for a long time.

9. You must write your exercise in pencil.

10. Mary is taking lessons from Miss Reese.

11. He will be here at five o’clock.

12. I have finished writing my exercise.

13. He is making much progress.

14. We shall see you tomorrow.

15. John used to study hard.

16. I dare ask him.

17. Mary will be promoted to the next class.

18. He has been in class since last month.

19. You ought to go.

20. I have a good library.

21. He is a man of honor.

B. 將下列句子變?yōu)榉穸ň洌?/p>

1. I felt much surprised at what I saw.

2. You sang better yesterday than today.

3. We heard of your success from your father.

4. It rained hard at twelve o’clock.

5. The sun rose at six o’clock this morning.

6. The fox fell into the trap last night.

7. The bees gathered much honey from those flowers.

8. This tree strikes its roots deep into the ground.

9. Some trees die before they are a hundred years old.

10. They told the boy to keep watch over the flock.

11. He strove to do his very best in his new class.

12. He gave as much as sixpence for that little book.

13. John made many mistakes in his examination.

14. It rains every day in New York.

15. I had time to study my lesson last night.

16. I understood everything he said.

17. He eats his lunch at twelve o’clock.

18. She wants to learn English.

19. He began his new work on the fifteenth.

20. Our classroom has three windows in it.

21. I am afraid in the dark.

22. He stayed in Taipei for a long time.

23. We need a rag in our room.

24. We use many books during our lesson.

25. John came to class ten minutes late.

26. Mary likes to study French.

27. They moved to Taichung.

28. William speaks English well.

C. 將下列否定句改為肯定句：

1. He did not see me secretly entering the room.

2. The sun does not rise at five o’clock.

3. The watchman did not run away from the thief.

4. We did not think John to be as clever as James.

5. He did not speak about the coldness of the classroom.

6. She does not think that a complaint should be made.

7. He did not feel ill during his absence from home.

8. The lightning did not strike the top of the house.

9. The noise in the street did not break my sleep.

10. He does not come here in time for his dinner.

11. They did not seek for the lamb that had been lost.

12. The dog did not hunt the deer without success.

13. The master does not expect me to finish this all at once.

14. This book does not seem to be as interesting as that.

15. He did not hear，I think，all that I said to him.

16. The child，walking along the bank，did not fall into the river.

17. This student did not strive to keep at the head of the class.

18. Bees do not gather much honey from these flowers.

19. I will not give this man any money.