—Why didn't you answer my phone when I phoned you at about 11 p. m. yesterday?
—I ___________and failed to hear the phone.
| A．might have slept | B．must be sleeping |
| C．might be sleeping | D．must have been sleeping |
--- _______ the plane have taken off on time?
--- I’m afraid not. So many flights were delayed due to the bitterly cold weather.
| A．Will | B．Should |
| C．Can | D．Must |
Nowadays, many parents are trying to either prevent their children from failure, or protect them from the knowledge ______ they have failed.
| A．when | B．where | C．what | D．that |
Last year alone, the temporary unemployment insurance lifted 2.5 million people out of poverty, and ________ the blow for many more.
| A．corrected | B．cushioned |
| C．compensated | D．corresponded |
___________the many ways illegal immigrants come into the United States every year, the vehicle crammed with crowds seems to be the method of choice lately. However, tragedies such as deaths on the journey to the destination, are sometimes reported nowadays．
| A．In | B．For | C．Of | D．On |
Not giving up when meeting with difficulties is a good quality, ______ you can benefit from.
| A．what | B．that | C．one | D．the one |