It's (is/has been) two years since he left China
It's (is) the first time that I have visited Shanghai
have/has been to … 曾经到过某地 have/has gone to … 去了某地4
Where there is a will, there's a way
It was not long before I forgot it all
need/want/require + to be done/doing 7
do nothing but do ; have no choice but to do8
The boy has his own idea of how to finish it
He is easy to deal with
/ You are lucky to get there on time
In order to/ to so as to find a good job, we should study well
too… to / enough to do12
He is too young to go to school
/ He is old enough to go to school
独立成分: To tell you the truth, … (句子)To be fair, … (句子) / To be frank, … (句子)To be sure, … (句子) / To make matters worse, … (句子)be to do / be about to do / be going to doh