__________at the door before you enter the office，or you’ll be considered impolite
#65893
A
Knocking
B
Knocked
C
Knock
D
To knock
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The floor is so dirty .Would you please ?
#59450
A
to mop up it
B
mop up it
C
to mop it up
D
mop it up
_____ the instructions very carefully when filling in the form.
#66031
A
Following
B
To follow
C
Follow
D
Followed
For more information about Cambridge,_____ our website at www.cambridge.org.
#66080
A
visiting
B
visit
C
to visit
D
visited
great progress it has made since Hong Kong returned to China in 1997.
#65921
A
Which
B
What
C
How
D
Whether