When the bell rings, we all go to the classroom to have class.
A.stops working
B.makes a sound
C.cries for help
Now my father _____ his bike to work every day instead of driving.
| A．ride | B．rode | C．rides | D．will ride |
By the end of last month, I _____ all the CDs of Justin Bieber.
| A．collect | B．collected | C．have collected | D．had collected |
You _____ lose your way if you walk alone in the mountains at night.
| A．may | B．need | C．should | D．ought to |
We didn’t start our discussion _____ everybody arrived.
| A．since | B．if | C．while | D．until |
Take the exam carefully, _____ you won’t get full marks.
| A．but | B．and | C．or | D．so |