People who cannot _____ between colours are said to be colour-blind.
| A．distinguish | B．compare | C．contrast | D．distribute |
Everything was placed exactly________he wanted it for the graduation ceremony.
(2012·天津，14)
| A．while | B．when |
| C．where | D．though |
He smiled politely ________ Mary apologized for her drunken friends. (2012·山东，27)
| A．as | B．if |
| C．unless | D．though |
I don’t believe we’ve met before，________I must say you do look familiar.
(2012·新课标全国，25)
| A．therefore | B．although |
| C．since | D．unless |
It’s not easy to change habits，________ with awareness and selfcontrol，it is possible. (2013·重庆，23)
| A．for | B．or |
| C．but | D．so |
Don’t turn off the computer before closing all programs，________ you could have problems. (2013·北京，22)
| A．or | B．and |
| C．but | D．so |