初中英语现在完成时 have/has+过去分词

初中英语 现在完成时 have/has+过去分词

现在完成时表示过去发生的事对现在有影响，或持续到现在的动作。

结构：have/has + 过去分词
标志词：already/yet/ever/never/just/before/since/for

I have already finished my homework.
She has never been to Beijing.
They have lived here for ten years.