问题描述:
关于过去时和完成时的区别
He (gazed at) the display for several minutes before re-entering his shop.括号内的为什么不能用 have gazed at.后面有before 说明 gazed at在re-entering 之前发生 这种情况(包括after)到底前后两句应该用什么时态.
He (gazed at) the display for several minutes before re-entering his shop.括号内的为什么不能用 have gazed at.后面有before 说明 gazed at在re-entering 之前发生 这种情况(包括after)到底前后两句应该用什么时态.
问题解答:
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