The Dongying-Hainan airline         for about 5 months. I have taken the flights three times.
#38883
A
is open
B
has opened
C
has been open
D
has been opened
推荐题目
More than 20 people ________ in traffic accidents ________ last week.
#37454
A
died; for
B
have been dead; since
C
have died; for
D
have been dead, for
It ____him half an hour to do his homework every day.
#40118
A
take
B
took
C
takes
D
taking
---- Look! Somebody_______ the sofa.---- Well, it wasn't me. I didn't do it.
#39251
A
is cleaning
B
was cleaning
C
has cleaned
D
cleaned