i don't know which one to choose.请造几个类似which ...to 的句子

i don't know which book to read
i don't know which one to buy
i don't know which bus to take

I don't know what to do next
I don;t know which one to buy,the bule one or the white one
could you tell me how to do the work
He did't tell me when to start the game
①Where to go is still a question.

到哪儿去仍然是个问题。（作主语）

②Which to choose is important.

选择哪一个是非常重要的。

③The question is how to learn English well.

问题是怎样才能学好英语。（作表语）

④I know where to find the boy.

我知道在哪里能找到这个男孩。（宾语）

⑤They know what to call it in English.

他们知道用英语叫它什么。（宾语）

⑥Li Ping doesn't know why to learn English.

李平不知道为什么学英语。（宾语）

⑦The doctor told him when to take the medicine.

医生告诉他什么时候服药。（宾语）

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