. Many Chinese students think science subjects are ______ foreign languages.
| A．more difficult as | B．less difficult than |
| C．much difficult than | D．so difficult as |
【2012河北】Studying in groups is necessary______ you want to do well in school.
| A．if | B．until | C．unless | D．though |
【2012 山东滨州】Mary, put on your coat, ______ you'll catch a cold.
| A．and | B．or | C．so | D．but |
【2012 山东临沂】The family had to stay at hotel, _____it was raining hard.
A because B. although C. until D. unless
【2012贵州贵阳】Teresa is ________ nervous ________ she can’t talk in front of the class.
A. such, that B. too, to C. so, that
【2012天津】A snake bit him ___________ he went to see a doctor at once.
| A．if | B．where | C．because | D．so |