Without the air to hold some of the sun's heat, the earth at night ________, too cold for us to live.
A.would be freezing coldB.would be freezing coldlyC.would be frozen coldD.can freeze coldly在线课程A
解析：
前半句是由without短语所表示的含蓄条件句，整个句子所表达的和事实相反，需用虚拟语气．指现在的情况，用would/could/should/might+动词原形；
freezing相当于副词，修饰cold．句意为“如果没有空气保存一部分太阳的热量，夜晚地球上就会太冷，令人无法居住．”