In our class, when the bell rang and the teacher closed his book, it was a ______ for everyone to stand up.
| A．signal | B．chance | C．mark | D．measure |
At the end of the eighteenth century, masks _________ completely.
| A．ban | B．had banned |
| C．banned | D．were banned |
We live in an age _________ more information is available with greater ease than ever before.
| A．why | B．on which |
| C．to whom | D．when |
Before he volunteered to direct traffic, Timoteo _________ lots of jobs.
| A．had had | B．has |
| C．have had | D．had |
—I looked after a group of fifteen French children.
—That _________ easy!
| A．mustn’t be | B．mustn’t have been |
| C．can’t have been | D．wasn’t |
Let him _________ ; he is a man of _________ temper.
| A．alone; variable | B．lonely; various |
| C．alone; various | D．lonely; variable |