We all should obey the rules. You ____talk loudly or smoke in the library.
A. don't have to B. mustn't C. can't D. shouldn’t
【答案】B
【解析】句意：我们都应该遵守规则。你不能在图书馆里大声讨论或者抽烟。考查情态动词用法。A表示不必，没必要。B表示不许(语气最强)。C表示不能，D表示不应该。根据句意，故选B。
题目：We all should obey the rules. You ____talk loudly or smoke in the library.
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