The Yellow River is _____ the Pearl River.
A twice long as B twice as long as
C as twice longer as D as long twice as
The tomato juice left brown ____ on the front of my jacket．
| A．spots | B．points | C．tracks | D．traces |
Most of the professors _____ to our school were from South Africa．
| A．invited | B．to be invited | C．being invited | D．had been invited |
—Alice, you look puzzled．Haven’t you understood it?
—Yes．I _____of another problem just now．
| A．had thought | B．have thought | C．thought | D．was thinking |
By looking at a problem in as many ways as possible, creative thinkers can find solutions that would _______ remain invisible．
| A．otherwise | B．yet | C．already | D．fo rever |
—What do you think of the performance today?
—Great! but a musical genius could perform so successfully.
| A．All | B．None | C．Anybody | D．Everybody |