The idea is that the nation ______ an unmanned spacecraft to explore the planet first.
A. sent
B. sends
C. send
D. must send
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It’s high time you ______.
A. start to work
B. would start to work
C. started to work
D. had started to work
“If I hadn’t practiced when I was younger,” the musician says,“I ______ able to play so well now.”
A. wouldn’t be
B. won’t be
C. wouldn’t have been
D. couldn’t have been
It is imperative that you ______ there in person.
A. are
B. were
C. be
D. will be
The atomic structure is, ______, a miniature solar system.
A. as they were
B. as if they were
C. as it were
D. as if are
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