题目内容：

I have never doubted -----he will come today,but I do doubt-----he will come on time.
A.that,that.B.whether,that.C.that,whether.D.whether,whether
麻烦再翻译一下整个句子

优质解答

1.C是正确答案.2.在否定句和疑问句中,doubt后面接that引导的宾语从句.例如：I've never doubted that you love me.3.在肯定句中,doubt 后面一般接whether 或if 引导的宾语从句.例如：I doubt whether they can swim ...

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