We have done things we ought not to have done and_____ undone things we ought to have done. 
#103904
A
left
B
leave
C
will leave
D
leaving
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“Mom_______ the supermarket,” the daughter said to her father.
#101779
A
has gone to
B
has been to
C
goes to
D
go to
The situation wasn’t very good, but I ________ many worse situations.
#102325
A
was experiencing
B
experienced
C
would experience
D
had experienced
– I’m leaving for Beijing next week.– How long ______ there?
#101707
A
have you stayed
B
are you staying
C
had you stayed
D
did you stay
It is the first time that Michel _______ the Summer Palace.
#99257
A
is visiting
B
visits
C
has visited
D
will visit