I was really anxious about you. You _______ have left home without a word.
| A．mustn't | B．shouldn't | C．needn't | D．couldn't |
He tried his best to solve the problem, _______ difficult it was.
| A．however | B．no matter | C．whatever | D．although |
With the World Cup at hand, _______ has been a heated discussion over which country the championship will go to.
| A．it | B．what | C．there | D．as |
---Besides being bright, he has always been working hard.
--- No wonder he _______ in almost all subjects.
| A．gets through | B．stands out | C．sets aside | D．holds up |
Only after he graduated _______ how much he loved his alma mater (母校) .
| A．he realized | B．he had realized | C．had he realized | D．did he realize |
The speech which he made _______ the project bored me greatly.
| A．being concerned | B．be concerned | C．concerned | D．concerning |