Before the first nonstop flight made in 1949,it______necessary for all planes to land for refueling.
#104556
A
would be
B
has been
C
had been
D
would have been
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 If I ____ more about diamond, I ____ cheated by that man.
#102987
A
had known, would not be
B
had known; wouldn’t have been
C
knew; would not have been
D
had known; would never be
. --Were you late for the film?--Very late. Half of it ________ by the time we ________ the cinema.
#102802
A
was shown; reached
B
had been shown; reached
C
was shown; had reached
D
had been shown; had reached