求答案及告诉我为什么，还有题目要注意的点．有多种解法的也请写出来
１、We often heard them sing the song in the class（改为被动语态）

2,The scientist still went on with his work（同义转换）

3,I borrowed a　dictionary from him last week（同义转换）
I borrowed him a dictionary last week.
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4,How interesting the news is!（同义转换）
The news is so interesting.
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5,It took the man five years to practise speaking English.（同义转换）

He spent five years to practise speaking English.
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６，"Did you sleep well last night?"David asked her（改为同义句）

7,H can finish his work at 12 a.m.. It's 11a.m. now.
（改为同义句）
He can finish his work in one hour
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8,The doctor told me to take the medicine 3 times a day（就划线部分提问）
How often did the doctor tell me to take the
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medicine?
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9,The children ate up all the apples．（改为被动语态）
All the apples were ate up by the children
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10,This is the most interesting film I have ever seen（改为同义句）

11,She didn't knwo what could be done（同义句）
She didn't know what to be done
－－－－－－－－－－－－－－－－－
12,If you don't work harder, you will fail in the exam（同义句）
Work harder,or you will fail in the exam.
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You will fail the exam ,without work harder
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13,Does Tom's mother have to make him tidy his room?
（被动语态）
14,I asked Dandy ,"How long will you stay here?"（间接引语）
I asked Sandy if she will stay here
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15,She couldn't win the came if they didn't help her
　（同义句）
She couldn't win the game without teir help.
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Help her,or she couldn't win the game.
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16,I think you are right（否定句）
I don't think you are right
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　 think
(什么是转移否定＜believe )

１６／２＂Do you like playing football?"Tom asked me(
间接引语）
Tome asked me if I like playing football.
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17,Mary has few friends（反意疑问句）
===
Mary has few friends,does/has she?
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为什么用ＨＡＳ　不用ＨＡＳＮ＇Ｔ？遇到什么词的时候会出现这种情况呢？请列出来

１８，Did he sing the song yeserday?（被动语态）
Did the song was sang yesterday?
--------------------------------

19,We found ti hard to finish the work in such a short time（宾语从句）

20,His roommate can hear him sing loudly at the bath time（被动语态）
He can be heard loudly by his roommate
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21,Some of the suits are too big and the others are too small（同义句）


22,My friend went to Bejing last year .She is still in Beijing now（同义句）

23,We had a very nice time（感叹句）

1,,It took the man five years to practise speaking English.（同义转换）
答：1,The man spent five years practising speakig English.
2,He spent five years to practise speaking English.


2,"Did you sleep well last night?"David asked her（改为同义句）
Divid asked her if she slept well the last night.

3,H can finish his work at 12 a.m.. It's 11a.m. now.
（改为同义句
答：1,He can finish his work in an hour
答：2,He is able to complete his work in an hour.

4,This is the most interesting film I have ever seen（改为同义句）
have never seen such an interesting film before.

5,She didn't know what could be done（同义句）
答：1,She had no idea what she could do .
2,She didn't know what to be done
She didn‘t know what to do.


6,If you don't work harder, you will fail in the exam（同义句）
答：
1,Work harder,or you will fail in the exam.
*2,You will fail the exam ,without working harder
Work harder，and you won’t fail in the exam.

*7,Does Tom's mother have to make him tidy his room?
（被动语态）
答：Is Tom had to make to tidy his room by his mother?
Does Tom have to be made to tidy his room by his mother？

8,I asked Dandy ,"How long will you stay here?"（间接引语）
答：1,I asked Dandy how long she would stay there.
2,I asked Sandy if she will stay here

9,She couldn't win the game if they didn't help her
　（同义句）
答：
1,She couldn't win the game without their help.


10,Do you like playing football?"Tom asked me(
间接引语）
Tome asked me if I liked playing football.

11,We found it hard to finish the work in such a short time（宾语从句）
答：We found that it was hard to finish the work in such a short time.

20,His roommate can hear him sing loudly at the bath time（被动语态）
答：He can be heard to sing loudly at the bath time by his roommate.
He can be heard loudly by his roommate
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21,Some of the suits are too big and the others are too small（同义句）
答：
The suits are either too big or too small.

22,My friend went to Bejing last year .She is still in Beijing now（同义句）
答：My friend has been in Beijing since last year.


23,We had a very nice time（感叹句）
答：What a very nice time we had!!
How nice the time we had was!