— Do you agree that lions and tigers ______ the cat family?
— I have no idea.
| A．belong | B．are belonged to | C．are belonging to | D．belong to |
The Yangtze River, China’s longest, has been affected by a severe drought, ________ the lowest level of rainfall this year since 1961．
| A．with | B．for | C．beyond | D．besides[来 |
Professor Smith, along with his assistants, _________on the project day and night to meet the deadline.
| A．work | B．working | C．is working | D．are working |
There was so serious a matter that I had no choice but _________ the police.
| A．called in | B．calling on | C．call for | D．to call in |
The new research team was led by the ________engineer.
| A．main | B．major | C．chief | D．primary |
—Will you come?
—________you promise not to invite Mary.
| A．As if | B．If only | C．Only if | D．Even if |