At school, some students are active ________ some are shy, yet they can be good friends with one another．
A．while
B．although
C．so
D．as
New technologies have made ________ possible to turn out new products faster and at a lower cost．
A．that
B．this
C．one
D．it
I am moving to the countryside because the air there is much fresher than ________in the city．
B．it
D．this
Attention, please．The last plane to London ________ off at 9∶00 pm．
A．take
B．takes
C．took
D．has taken
It has been proved ________ eating vegetables in childhood helps to protect you against serious illness later．
A．if
B．because
C．when
D．that
Please remind me ________ you are going．I may be in time to you off．
A．where
B．when
C．how
D．what
The doctor almost lost hope, but the patient finally ________．
A．gave up
B．pulled through
C．gave in
D．got through
It was nice of Kathy to help us a lot．We wouldn't have completed the task ________．
A．however
B．otherwise
C．therefore
D．though
After the accident, Christopher sometimes felt sorry ________himself, but never thought ________committing suicide．
A．at, with
B．with, in
C．for, of
D．in, for
In some places women are expected to earn money________ men work at home and raise their children．
A．but
B．while
C．because