句子的转换就是将一种句式变成另外一种句式，或者用不同的方法表达相同的语意，使句型多样化，借以提升写作的效果。例如形容词和副词可以有不同程度的比较而仍然保持原意。

　　下面的第一句是原级，可以变成第二句：比较级：

　　(1) Nancy is not so great as lrene.

　　(2) Irene is greater than Nancy.

　　同样的，主动语态可以变成被动语态而原意犹存。例如(3)是主动语态，(4)是被动语态，两句语意不变，只是重点改变。

　　(3) Mr Lin gave the good student a prize.

　　(4) The good student was given a prize by Mr Lin.

　　还有，一种词类也可以变成另一种词类并保留原意。例如：

　　(5) a. The customer examined the jewels very carefully.

　　b. The customer examined the jewels with great care.

　　(6) a. She tried to sing her song in an interesting way.

　　b. She tried to sing her song interestingly.

　　此外，一种句子也可变成另一种句子：

　　1. 简单句变成复杂句

　　(Simple Sentence → Complex Sentence).

　　(1) Do you know the gentleman with a long hair? → Do you know the gentleman who has a long hair?

　　(2) In case of an emergency, ring the bell on the door. → If there is an emergency, ring the bell on the door.

　　(3) The accused man confessed his guilt. → The accused man confessed that he was guilty.

　　(4) Walking along the road, Tony ran into an old friend. → While Tony was walking along the road, he ran into an old friend.

　　2. 复杂句变成简单句

　　(Complex Sentence → Simple Sentence)

　　(5) We visited a hut where a hermit lived. → We visited a hermit′s hut.

　　(6) Jim was so surprised that he could not utter a word. → Jim was too sunprised to utter a word.

　　3.并列句变成复杂句

　　(Compound Sentence → Complex Sentence)

　　(7) The dogs were wounded but they went on fighting. → Although the dogs were wounded, they went on fighting

　　(8) The couple went to Johor Baru and the maid looked after their residence. → When the couple went to Johor Baru, the maid looked after their residence.

　　4. 简单句变成并列句

　　(Simple Sentence → Compound Sentence)

　　(9) I must work very hard to achieve something. → I must work very hard and then achieve something.

　　(10) In spite of illness, Jason came to office as usual. → Jason was ill but he came to office as usual.