单项选择题

A leap year(闰年) ______ once every four years.

A．occurred
B．occurreds
C．is occurred
D．was occurred
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单项选择题
The temple is on the edge of lake ______ has been made by the dam.
A．where
B．when
C．who
D．which
单项选择题
We'll meet again tomorrow and ______ a decision then.
A．do
B．find
C．decide
D．make
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