英语语法辨析:现在完成时知识点汇总
标志:have / has + 动词的过去分词
1. 表示一个过去发生并已完成的动作对现在产生影响或结果,强调的是现在的状况(表示“已完成”)。
如:
He has left the city.
Someone has broken the window.
2. 表示一个动作开始于过去,持续到现在,也可能还会继续持续下去(表示“未完成”)。
I have been busy since last week.
He has taught in our school for 30 years.
I’ve finished half so far.
注意瞬间动词通常是不能用现在完成时表持续性的,但其否定结构则可以。
如:
She hasn’t seen you for ages.
His father hasn’t touched beer for a whole week.
3. 表示过去到现在为止反复发生的动作或多次出现的状态,常与表示频度的副词always, often, every day等连用。
如:
I have often heard that he is the cleverest person in that company.
4. 在时间和条件状语从句中,现在完成时表示将来某时完成的动作。
如:。