The young man stopped and looked back as if ______ whether he was being followed.
| A．seeing | B．to have seen | C．having seen | D．to see |
----Have you got the result?
----No, It will be some time ________we know the result.
| A．when | B．since | C．if | D．before |
. Little ______about his own health though he was very ill.
| A．he cared | B．he cares | C．does he care | D．did he care |
The light will be thrown ______ the cause of cancer by research that is now in progress.
| A．to | B．upon | C．in | D．for |
—Why was he unhappy yesterday?
—A letter from home ______ an attack of homesickness.
| A．set off | B．set out | C．set about | D．set up |
______great progress Jim had made in _______ time!
| A．What a ; such a short | B．What ; so short a |
| C．How a ; such a short | D．How; such short |