Question

before可以和延续性动词在一起用吗

Answer 1

你好
1.主句的谓语为非持续性动词的肯定式时，只能用before。例如：
He left for Wuhan before eight. 八点前他就动身去武汉了。
2.主句的谓语为非持续性动词的否定式时，用before或until均可，且意义相同。例如：
Susan didn’t go to bed until / before she finished her homework. 苏珊直到完成家庭作业才去睡觉。
3.主句的谓语为持续性动词时，用before或until均可，但意义有所不同。试比较：
He watched TV until his mother came back. 他看电视一直到妈妈回来为止。(侧重“行为到……为止”)
He watched TV before his mother came back. 妈妈回来之前他在看电视。(侧重“在……之前的行为”)
4.主句的谓语为持续性动词的否定式时，常用before而较少用until。例如：
I won’t say anything before my lawyer comes. 在我的律师来之前，我什么也不会说的。
5.当“not...until”结构用于倒装句或强调句时，一般还是要用until。例如：
Not until next month can we move in. 直到下个月我们才能搬进去。
希望可以帮到你

Answer 2

延续性动词与非延续性动词之间的转换：leave --- be away, borrow --- keep, buy --- have, begin/start --- be on, die --- be dead, finish --- be over, join --- be in+组织, be a member of+组织, open sth --- keep sth open, fal。