单项选择题

There is supposed to be a safety _______ which makes it impossible for trains to collide.

A．appliance
B．accessory
C．machine
D．mechanism
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单项选择题
If a person talks about his weak points, his listener is expected to say something in the way of _______.
A．persuasion
B．remedy
C．encouragement
D．compromise
单项选择题
Your child is too young to play football. You had better have him _______ table tennis instead.
A．take for
B．take up
C．take in
D．take over
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