单项选择题

A considerable amount of time and money has been invested in ______ this system.

A．defining
B．implying
C．reducing
D．perfecting
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单项选择题
Most of them had visited the invalid often during the past few months, marveling at his ______ spirit and his unfailing good temper.
A．variant
B．gallant
C．pertinent
D．solitary
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