All substances, ＿＿＿＿＿ solids, liquids, or gases, are made up of entirely atoms. A.whether they B.whether C.whether are they D.whether are 题目和参考答案——青夏教育精英家教网—

题目内容

All substances, ＿＿＿＿＿ solids, liquids, or gases, are made up of entirely atoms.

A.whether they B.whether C.whether are they D.whether are

解析:

在带有状语从句的复合句中，如果从句与主句的主语一致，且从句中含有be动词，则可以省略从句的主语及be动词。此处从句中省略了they are。

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