Ladies and gentlemen, please fasten your seat belts. The plane  ________.
#104000
A
takes off
B
is taking off
C
has taken off
D
took off
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I was out of town at the time, so I don’t know exactly how it _______. 
#104951
A
was happening
B
happened
C
happens
D
has happened
She ______ on a new novel ever since this summer and it is supposed to ______ at the beginning of 2011.
#102453
A
had worked; be published
B
had been working; have published
C
has worked; publish
D
has been working; be published