单项选择题

A new technique ______, the yields as a whole increased by 20 percent.

A．working out
B．having worked out
C．having been worked out
D．to have been worked out
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单项选择题
These shoes are too big. Ask the clerk to bring you a smaller ______.
A．suit
B．set
C．one
D．pair
单项选择题
To our ______, Geoffrey's illness proved not to be as serious as we had feared.
A．anxiety
B．relief
C．view
D．judgment
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