这个定语从句 The man who is reading a book 之所以是错的,
是因为句子的结构不完整,这里主语是he man,定语为who is reading a book,
缺少谓语,可以改成这样：
The man who is reading a book is my English teacher.正在读书的那个男人是我的英语老师.
能看明白么?
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