We must know what we should do and what we should avoid _______ a good impression on others in public places.
| A．to leave | B．leaving | C．to have left | D．leave |
It is the first time that I _______ this kind of tasty moon cake.
| A．enjoy | B．have enjoyed | C．has enjoyed | D． am enjoying |
Busy as the working mother is, she still_____ a lot of time to her children.
| A．devotes | B．spends | C．offers | D．provides |
As far as I know, the new highway is about______ the former one.
| A．as wide as three times | B．three times the width of |
| C．longer than twice | D．the width of three times |
Was it in 2002 __________ he was still at middle school __________ the boy became expert at computer?
| A．that; where | B．when; where | C．that; when | D．when; that |
The professor wants the students to pay more attention to the festivals ______ in other parts of the world.
| A．celebrating | B．having celebrated | C．celebrated | D．to celebrate |