There______ a number of natural mysteries in the world that even make scientists ______.
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A
exists; confusing
B
are existed; confused
C
exist; confused
D
exist; confusing
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The number of the students in our class __________ to 54.
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A
picks up
B
adds up
C
takes up
D
turns up
The Governor demanded that all the proposals _______ on May 1st.
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A
must be submitted
B
be submitted
C
submitted
D
were submitted