When, while, before, after, till, once, as soon as, so long as, by the time, if, in case (that), unless, even if, whether, the moment, the minute, the day, the year, immediately等引导的时间状语从句,条件句中,用一般现在时代替将来时。例如:
He is going to visit her aunt the day he arrives in Beijing. 他一到北京,就去看他姨妈。
典型例题
(1)He said he________me a present unless I_______ in doing the experiment.
A. had not given; had not succeededB. would not give; succeeded
C. will not give; succeed D. would not give; will succeed.
答案B. 在时间,条件或让步主语从句中一般不用将来时。本题有He said,故为过去式。主句用将来时,故选B. 此处用一般过去式代替了过去将来时。
(2) 表示现在已安排好的未来事项,行程等活动。例如:
The museum opens at ten tomorrow.博物馆明天10点开门。(实际上每天如此。)