第1个回答 2006-06-01
while引导时间状语从句,一般强调从句的动作正在发生,或主句从句的动词同时进行。如:I was doing my homework while my mother was cooking.
延续性动词是指动词可以延续一段时间的词,如live,study,have, keep等。结束性动词也叫终止性动词或瞬间动词,指动词不能持续一段时间。如:buy,die,borrow,lend.
e.g.I bought a new pen last week.
I have had the pen for a week.
He borrowed the book two weeks ago.
He has kept the book for two weeks.本回答被提问者和网友采纳