____ red is a symbol of warmth, it can sometimes make people feel uneasy or even frightened.
| A．As | B．Since | C．If | D．While |
They were surprised that a four-year-old boy should work out such a difficult problem
____they themselves couldn’t.
| A．once | B．then | C．while | D．if |
I think you ought to end it____it is too late,or you’l lkill yourself.
| A．even if | B．before | C．so that | D．once |
The girl go herself into a serious situation____she was likely to lose control over the
motorbike.
| A．where | B．which | C．while | D．why |
.Girl____,she is much naughtier than a boy.
| A．although she was | B．though she is |
| C．though was she | D．although was she |
Mr Smith was so angry at all____Bill was doing____he walked out angrily.
| A．that;what | B．that;that | C．which;which | D．what; that |