开篇语
It is the first time that sb. has done sth.
It was the first time sb. had done sth.
H ardly had sb. done sth. when sth. happened.
No sooner had sb. done sth. than sth. happened.
sb. is always doing sth.
表说话者说话时的一种情感色彩，赞扬、责备或批评。
表位移方向的动词的现在进行时表将来。
I’m leaving for Shanghai tomorrow.
by+将来时间状语 或表将来时态的句子，要用将来完成时态；
by+过去时间状语或表过去时态的句子，要用过去完成时态。
