大學(xué)英語四級(jí)語法精要
Ⅰ動(dòng)詞(時(shí)態(tài),語態(tài),用法,省略,一致性等)
1. 時(shí)態(tài)
1)現(xiàn)在完成進(jìn)行時(shí)態(tài) (have/has been + -ing 分詞構(gòu)成): 動(dòng)作或狀態(tài)從過去某時(shí)開始,繼續(xù)到現(xiàn)在,可能繼續(xù)下去,也可能剛剛結(jié)束.
I’ve been writing letters for an hour.
I’ve been sitting in the garden.
2)過去完成進(jìn)行時(shí)(由had been + ing分詞構(gòu)成): 過去某個(gè)時(shí)刻以前一直在進(jìn)行的動(dòng)作
I’d been working for some time when he called.
We had been waiting for her for two hours by the time she came.