You should study harder______ it is too late to catch up.
#55841
A
if
B
when
C
after
D
before
推荐题目
---- Ring me up you come to my house, will you? ----Sure, I will.
#58294
A
though
B
while
C
before
D
until
—How long have you known the doctor ? — he helped me three years ago.
#58435
A
When
B
Before
C
Because
D
Since