It was not until he got home __________ Mr. Brown realized he had left his keys in his office.

A．that          B．when        C．where       D．before

When _________, the new school buildings can hold as many as 10,000 students.

A．being completed                                         B．completed           

C．to be completed                                          D．is completed

－Who are the teenagers gathering at the school gate?

－Well, if you ____________ know, they are all my visiting students.

A．shall         B．can           C．may         D．must

___________ is known to us all is that the old scientist, for ___________ life was hard in the past, still works very hard in his eighties.

A．As; whom               B．What; whom           C．It; whose         D．As; whose

The workers are so ___________ to the noise of the machine that they don’t even notice it during their work.

A．a(chǎn)ccustomed            B．subjective         C．familiar     D．a(chǎn)ssociated

Years ago we didn’t know this, but recent science ____________ that people who don’t sleep well soon get ill.

A．showed    B．has shown              C．will show         D．is showing

The doctor would allow him to go home __________ he remained in bed.

A．a(chǎn)s though                                                   B．for fear that        

C．on condition that                                         D．a(chǎn)s far as

Peter’s sudden death was a great blow to Mary and it took her quite a while to ___________ the grief.

A．run over          B．take over          C．turn over         D．get over

His body temperature has been _________ for three days, the highest point reaching 40℃.

A．uncommon      B．disordered        C．a(chǎn)bnormal  D．extraordinary

Good technique in medicine means less pain and fewer deaths and, _____ it is our duty to master it.

A．Altogether        B．therefore          C．otherwise         D．however