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There be句型
存在动作，改为定语、分词（现在分词、过去分词）
常见错误
错：There are many people play in the garden.
定语从句：There are many people who are playing in the garden.
分词：There are many people playing in the garden.
错：There are many teachers have a meeting in the classroom.
定语从句：There are many teachers who are having a meeting in the classroom.
分词：There are many teachers having a meeting in the classroom.
There are many books which are recommended by teachers.
There are many books recommended by teachers.
