This is a book that is worth reading.

　　→This is a book worth reading. 这是一本值得看的书。

　　(2) 定语从句简化为现在分词或现在分词短语作前置或后置定语。

　　The man who is standing under the tree is our English teacher.

　　→The man standing under the tree is our English teacher.

　　站在树下面的那个人是我们的英语老师。

　　I saw the house that was burning at that time.→I saw the burning house at that time.

　　当时我看到那房子在燃烧。

　　(3)定语从句简化为过去分词短语作后置定语。

　　I like to see the films which are directed by Zhang Yimou.→I like to see the films directed by Zhang Yimou. 我喜欢看张艺谋导演的电影。

　　She is the girl who was praised at the school meeting.→She is the girl praised at the school meeting. 她就是在校会上受表彰的那个女孩。

　　(4)定语从句简化为不定式作后置定语。

　　He is always the first person that comes to school.→He is always the first person to come to school.他总是第一个到校。

　　The report which will be given tomorrow is important to us.→The report to be given tomorrow is important to us. 明天要作的报告对我们很重要。

　　(5)定语从句简化为what 从句。

　　I couldn't remember the words that he said.→I couldn't remember what he said.

　　我记不得他说的话。