Tell me _______how it came about that you were 20 minutes late for class. You needn’t go into details.
| A．in advance | B．in brief | C．in total | D．in vain |
---Would you mind if I opened the door?
--- ________________.
| A．Yes, go ahead | B．No, go ahead | C．Yes, please | D．Never mind |
It is demanded that you ____ at six.
| A．will arrive | B．arrive | C．arrived | D．would arrive |
At present，there is little doubt ________ short message plays an increasingly important role in our lives．
| A．whether | B．if | C．that | D．which |
— Are you a teacher?
— No, but I ______. I worked in a middle school for three years.
| A．am | B．will | C．do | D．was |
— Is your mother going to the supermarket？
— No，______.
| A．she doesn’t | B．she’s cooking | C．she gets by bus | D．to a tailor’s shop |