发布网友 发布时间:5小时前
我来回答
共1个回答
热心网友 时间:9分钟前
had + past perfect tense had+过去完成时I had finished doing homework yesterday.我昨天就已经做完作业了。has + present perfect tensehas+现在完成时He has eaten some biscuit.他已经吃过一些饼干了。