单项选择题
The achievements of the greatest minds in science could never have been reached if it had not been for the patient and accurate work of hundreds of other people（）.
A．has it not been B．if it had been C．if hasn't been D．had it not been
单项选择题 No thing fuels cynicism for watching two titanic institutions squabble over their reputations（）.
单项选择题 The general manager demanded the job will be completed before the National Day（）.
单项选择题 No such weapons were used and none been found（）.
