conj 直到……之时;在……以前(before or up to the time when)：go straight on～you come to the post office/you reach the station 一直向前走，走到邮局/车站(再停下);I propose waiting～the police get there. 我建议一直等到警察来。Don't promise Harry～we've had time to think about it. 在我们有空考虑这个问题之前，不要对哈利许诺。〖同〗until;

prep 直到……之时，直至(up to the time of)：wait/talk～ten o'clock/next Monday/tea/dawn/nearly midnight 等/谈到10点钟/下周一/下午茶的时候/黎明/将近午夜;fight～death 战斗至死;work from morning～night/from Monday～Friday 从早到晚/周一到周五一直工作;not get back～late at night/after the lesson 直到夜深/上完课才回来;I don't know～now that you were ill. 直到现在我才知道你病了。〖同〗until;

up till 到……为止：I've lived in the country all my life up～now. 到现在为止，我一辈子住在农村。

【注意】till和until 基本相同，但句首一般不用till，而用until。