Many college students are willing to work in Western China after graduation _______, poor and backward as it is, more opportunities of employment are available.
| A．which | B．when | C．that | D．where |
Not until I began to work ______how much time I had wasted.
| A．didn’t I realize | B．did I realize | C．I didn’t realize | D．I realized |
Not until the early years of the 19th century______ what heat is.
| A．man did know | B．man knew | C．didn’t man know | D．did man know |
_____ he realized it was too late to return home.
| A．No sooner it grew dark than | B．Hardly did it grow dark when |
| C．It was not until dark that | D．It was until dark that |
So little _____ agree on the plan that they could not settle their difference.
| A．did they | B．do they | C．they did | D．they did not |
We were lucky enough， for no sooner _____ home _____ it rained.
| A．we returned， and | B．we had returned， when |
| C．did we return， when | D．had we returned， than |