__________at the door before you enter the office，or you’ll be considered impolite
#65893
A
Knocking
B
Knocked
C
Knock
D
To knock
推荐题目
_____ for the young man to spit in the subway!
#65984
A
How bad manners it is
B
How bad manners they are
C
What bad manners they are
D
What bad manners it is
—Look at the children in the lake. They are playing happily Let’s _____,too.—Good idea!
#59436
A
go hiking
B
go camping
C
go boating
D
go sightseeing