In the U.S, ______a tip is thought to be polite when paying the bill. 
#91505
A
leave
B
having left
C
leaving
D
being left
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Nobody likes ______.
#97512
A
to speak ill of
B
to be spoken ill of
C
speaking ill of
D
spoken ill of
You are silly not       your door.
#92231
A
to lock
B
to have locked
C
locking
D
having locked