Perseverance is a kind of quality --- and that’s ________ it takes to do anything well.
A．why B．that C．which D．what
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
