22. —Mr. Smith _____ in Russia for 10 years.
—No wonder he can speak Russian fluently and now teaches Russian in a Chinese college.
had stayed B. has stayed C. stayed D. stays
Paper bags produced every year are ______ the world’s production of vehicles.
| A．as three times heavy as | B．three times weight of |
| C．three times the weight of | D．three times as heavier as |
—Well, I do think the ipad is smart, convenient and intelligent.
—________.
| A．So it is | B．So is it | C．So does it | D．So it does |
You have to believe in yourself. Self-confidence is _____ to success.
| A．essential | B．combined | C．similar | D．compared |
His spare time is made full use_______ law.
| A．to study | B．study | C．of studying | D．of to study |
Mark needs to learn Chinese _______ his company is opening a branch in Beijing.
| A．unless | B．until | C．although | D．since |