it is in the classroom that he lost his book.

it is in the classroom that he lost his book.
it is the classroom where he losst his book in.这两个句子有错没得.是不是一个强调句 一个定语从句.谁给我讲讲强调句和定语从句中的被强调部分和定语从句的先行词的区别.有十名异同.不要给我说那些去掉被强调部分还是一个句子的救生强调句.那个我知道.