Mr. Smith didn’t go to the party because he had a lot of experiments _____. 
#90778
A
do
B
did
C
done
D
to do
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“Things________never come again!” I couldn’t help talking to myself.
#94217
A
lost   
B
losing
C
to lose   
D
have lost
—Thank goodness, you are here! What _____ you?—Traffic jam..
#96612
A
kept
B
is keeping
C
keeps
D
had kept