I have known him for two years.為啥不對?
I knew him two years ago,過去式,只能說明,你在兩年前是認識他的,或表達我在兩年前就已經(jīng)認識他了.
你們倆個到底什么時候初次認識對方的,這句話里沒有表達清楚.
最常用地道的表達“我兩年前（初次）認識他的”是：I got to know him two years ago."get to know"就有初次認識的意思了.或者用完成時,換一種方法說,我們是朋友已經(jīng)兩年了,We have been friends for two years.
“I met him two years ago.”跟I knew him two years ago類似,還是不對的.只能說明你兩年前遇見他.不能說明你們什么時候最初認識.如果要用met,應該加上first,I first met him two years ago,就清楚的表達出我最初是兩年前見到他的.
know 狀態(tài)性動詞,它后面可以跟表示時間延續(xù)的狀語.
meet 終止性 或點動詞,它后面不可以跟表示時間延續(xù)的狀語.
I have known him for two years.【正確】【原因是：know屬于狀態(tài)性動詞】
I knew him two years ago.【錯句】【原因是：你認識他就隨時能夠認識他,沒有動作,比如你的同學肯定認識吧,不存在時間問題.所以改成下句就對了】
I met him two years ago.【正確】
I know him.我認識他.【正確】