Being a teacher always encouraging students to think for themselves, I won't tell them answers until they __________ on a math problem for more than an hour.
#101395
A
have worked
B
will have worked
C
will have been working
D
had worked
推荐题目
---You phone number again? ---I ___ quite catch it---It is 3453789..
#104023
A
didn’t
B
couldn't
C
don’t
D
can’t
We_______on this project for four hours. Let’s have a rest.
#103758
A
are working
B
have been working
C
worked
D
had worked