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搜题
【单选题】
What happened during the past four weeks?A.
The man has bought a new house.
B.
The man's company has moved to a new building.
C.
The man's family has moved to a new building.
D.
Nothing special.
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皮皮学刷刷变学霸
举一反三
【单选题】--- When did your father ______ Guangzhou? --- Last night.
A.
arrived at
B.
get to
C.
reached
D.
went
【单选题】When my mother returned last night, I ____ a book.
A.
read
B.
am reading
C.
was reading
D.
am going to read
【简答题】脉冲的另一个重要参数是( ),常用脉宽和周期的比值表示。