We don’t allow ____ in the office. But you are allowed ______ in the open air. 
#96186
A
smoking; smoking
B
to smoke; to smoke
C
smoking; to smoke
D
smoke; smoking
推荐题目
 Paul does nothing but _____ all day long.
#97507
A
play
B
to play
C
playing
D
played
 She said she was sorry _____ the train, so she had to stay here for another day.
#98326
A
missing
B
having missed
C
to miss
D
to have missed
Genius is a complicated concept ,          many different factors.
#90684
A
involved
B
involving
C
to involve
D
being involved