（2010·云南模拟）The tomato juice left brown ____ on the front of my jacket．
A．spots B．points C．tracks D．traces
（2010·云南模拟）Most of the professors _____ to our school were from South Africa．
A．invited B．to be invited C．being invited D．had been invited
（2010·重庆模拟）—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
（2010·重庆模拟）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．forever
（2010·南昌二模）—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
(2010·天津模拟)Get out of here at once. _________ not, I’ll phone the police.
A. Since B. If C. Why D. When
