—Do you know where David is? I couldn't find him anywhere.
—Well, he ______ have gone far—his coat's still here.
| A．shouldn't | B．mustn't | C．can't | D．wouldn't |
With more forests destroyed, huge quantities of good eartheach year.
| A．is washing away | B．is being washed away |
| C．are washing away | D．are being washed away |
How did it that you made such a silly mistake?
| A．bring about | B．come about |
| C．come across | D．come on |
He was told that it would be at least 3 more monthshe could recover and return to work.
| A．until | B．as soon as | C．since | D．before |
When asked to explainhe did to make his students so fascinated with his lessons the teacher paused and thought deeply.
| A．what it was that | B．that what it was |
| C．what was it that | D．that what was it |
Robert is saidabroad, but I don’t know what country he studied in.
| A．to have studied | B．to study |
| C．to be studying | D．to have been studying |