The freezing point is the temperature __________ water changes into ice.
A．atwhich B．when C．inwhich D．ofwhich
Don’t talk about such things _______ you are not sure about.
A．which B．that C．as D．what
Hurry! The train _______. You know it _____at 8:30am. .
A．leaves; leaves B．is leaving; leaves
C．leaves; leaving D．is leaving; is leaving
With the help of high technology, more and more substances _________ in the past years.
A．discovered B．have discovered
C．had been discovered D．have been discovered
Jim is the only one of the policemen in his office who __________ the award.
A．have won B．win C．has won D．was to win
The company the girl used to work ________ was shut down last month.
A．for that B．for C．for whom D．/
