You can’t complain about being left out ______you don’t make any effort to share your joys and sorrows with others.
| A．once | B．unless | C．when | D．though |
______ scientists know where a storm will happen, winds will suddenly change, carrying the storm to a new direction.
| A．Even if | B．Since | C．Despite | D．Unless |
When doing your history homework on the Civil War by typing in details to Google, a list of related books will ______ .
| A．come on | B．come up | C．come down | D．come across |
He _______ to go to Tsinghua University to study after graduating from high school, so he is working very hard.
| A．demands | B．defends | C．desires | D．designs |
The thief went into the house at midnight, only ______ by the policemen hiding there.
| A．to catch | B．catching | C．to be caught | D．caught |
. It is because English is being widely used at present _______.
| A．why we learn it hard | B．that we learn it hard |
| C．which we must learn | D．when we should learn |