—Why does the lake smell terrible?—Because large quantities of water ________.
#99571
A
have polluted
B
is being polluted
C
has been polluted
D
have been polluted
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 I ______, but I was prevent by the heavy rain.
#104168
A
had meant coming
B
had meant to come
C
meant to come  
D
meant coming
 My cousin went to Canada two years ago. He ____ there for a few months and then went to America.
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A
worked
B
would work
C
would be working
D
has been working
By the time Fred gets back home, his girlfriend       for London to study.
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A
will have left
B
leaves
C
has left
D
will leave