this is my pen.you may h_____ it空里填什么？

This is the way____he did it.，为什么填that或which，而不是h~

定语从句，意思就是这是他做这件事的方法，the way是先行词，he did it修饰先行词。

This TV program is helpful . You should watch it when you have time.
这个电视节目很有帮助，你应该在有空的时候看看。

This is my pen. You may have it.

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