---What’s wrong with him? He is so sad.
---He was ____ at not being invited to the party.
| A．nervous | B．worried | C．upset | D．stubborn |
_____ of the students who took part in the military training is 450.
| A．A number | B．A lot | C．A few | D．The number |
—How many times have you been to China?
—In fact, it is the first time that I__________ here.
| A．was | B．have been | C．had been | D．am |
—I missed the first part of the film. It was really a pity.
—You __________ home half an hour earlier.
| A．should go | B．must have gone |
| C．should leave | D．should have left |
Please __________ the numbers and I’m sure they will __________ more than 1, 000.
| A．add up; add to | B．add up; add up |
| C．add up; add up to | D．add to; add up |
He made a mistake, but finally he solved the problem __________ it got worse.
| A．until | B．before | C．when | D．as |