－Have you known Dr Jackson for a long time?－Yes，since she the Chinese Society．
#102003
A
has joined
B
joins
C
had joined
D
joined
推荐题目
Space exploration began in the 1960s, and since then about five hundred people into space.
#101989
A
have traveled
B
traveled
C
had traveled
D
are traveling
Whatever may happen, go on until you succeed, and you _______ what life is all about.
#102853
A
will know
B
know
C
have known
D
will have known
We must give up the project now. We _____ money.
#101247
A
are running out of
B
will run out of
C
had run out of
D
have run out of
They each other for 5 years.
#103960
A
have been in love with
B
have fallen in love with
C
are in love with
D
fell in love with
After the examination，my teacher told me that failure _______the mother of success.
#102951
A
was
B
is
C
be
D
been