She is a quiet girl at school，but sometimes she _____ be very naughty.
| A．should | B．would | C．can | D．will |
______ is obvious that reading in bed does great harm to your eyes.
| A．This | B．That | C．They | D．It |
Anything ______ could be found has been used to repair the damaged bridge.
| A．that | B．which | C．when | D．what |
The concert last month was ______ that all the audience wanted to attend it once again.
| A．so success | B．such success | C．so a success | D．such a success |
______ the stage design was terrible, the special effects were disappointing.
| A．As | B．Unless | C．Although | D．As soon as |
If there ______ no water or air on the earth, all living things would die.
| A．is | B．were | C．are | D．will be |