_____ we admit that there are still some problems about NMET, we don't mean that it is of no use.
| A．Until | B．While | C．As | D．Unless |
I was in the baths , ______ I didn’t hear the telephone, which was ringing several times.
| A．as a result of | B．with the result that | C．resulting in | D．resulting from |
She was so _____ in her job that she didn’t hear anybody knocking at the door.
| A．devoted | B．attracted | C．drawn | D．absorbed |
Our professor told us that salt water _____ at a lower temperature than fresh water.
| A．is freezing | B．was frozen | C．freezes | D．froze |
Until recently historians assumed that calendars ________ with the advent of agriculture.
| A．came to existence | B．came to existing |
| C．came to exist | D．were existential |
. ________ when the boulders suddenly disappeared.
| A．So relieved we felt | B．How relieved we felt |
| C．What a relief we were feeling | D．How we felt relieved |