A heavy learning burden leads to unhealthy behaviors such as poor eating habits, which ___ damage the health of students.
A．in its turn B．in return C．in turn D．by turns
How did you ___ to paint the whole house in a week?
A．try B．manage C．win D．succeed
Black clouds had completely ___ the sun.
A．blocked off B．broken out C．blocked out D．broken off
It was an unpleasant subject ____ we _____ for a long time.
A．about which…discussed B．about which…argued
C．over them…argued D．which…argued
It must have rained last night, ________ the ground is wet now.
A．for B．because C．since D．now that
The serious expression of the captain kept his crew _________.
A．in the distance B．from a distance C．in a distance D．at a distance
