Not until the early years of the 19th century ________ what heat was.
| A．man did know | B．did man knew |
| C．didn't man know | D．did man know |
_____ matters most in learning English is enough practice.
| A．What | B．Why | C．Where | D．Which |
— Are you _____with doing a lot of homework everyday?
—Sometimes I am. But as a student , we have to do so at present.
| A．satisfied | B．encouraged | C．bored | D．pleased |
He wrote a lot of novels, none of _____ was translated into a foreign languages.
| A．them | B．where | C．that | D．which |
An offer of a reward has caused many students in our school _____ actively in the competition.
| A．participate | B．participated | C．participating | D．to participate |
_____ alone in the dark room, the little girl was so frightened as to cry loudly.
| A．Leaving | B．Left | C．Having left | D．To be left |