He was a teacher before he left his hometown
What has________ him since then?
| A．made of | B．become of | C．brought up | D．happened on |
People who often stay up too late are more likely to die of heart disease，________ a study.
| A．with the help of | B．because of | C．according to | D．as a result |
He picked up an envelope________50 dollars in it.
| A．containing | B．contained | C．which contains | D．which was contained |
I didn’t hear the phone. I ________ asleep.
| A．must be | B．must have been | C．should be | D．should have been |
—Does he know how to work out the problem?
—Yes，he has ________ a good idea to solve it.
| A．caught up with | B．kept up with | C．come up with | D．put up with |
The trip will take about five months；it will be a long time ________ we meet them again.
| A．after | B．before | C．since | D．when |