Being poor, they had to build a__________ shelter out of tree trunks.
| A．common |
| B．normal |
| C．primitive |
| D．formal |
_____________ worries me the way he keeps changing his mind.
| A．This | B．That | C．What | D．It |
—How much if I wan to take one?
—You can take as many as you like because they are free of _____.
| A．cost | B．charge | C．money | D．pay |
The young student is ____as a writer. It’s_____to all his teachers.
| A．success, surprise | B．a success, a surprise |
| C．a success, surprise | D．success, a surprise |
Do you know the___of the saying I just quoted?
| A．source | B．resource | C．course | D．cause |
一Let’s try operating the machine right now．
一Wait．Better read the ______ first．
| A．instructions | B．explanations | C．information | D．introduction |