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
Some ______ good luck brought us nothing but trouble.
A．seemingly
B．satisfactorily
C．uniformly
D．universally
单项选择题
He is a very ______ character; he is never relaxed with strangers.
A．self-confident
B．self-conscious
C．self-evident
D．self-serving
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