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来源: 于 2010-12-30 14:31:28 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

How come 有没有过去时？

比如说, How come he failed the exam?

>>>>>

"How come" = (informal) "why".

How come he failed the exam?

Why did he fail the exam?