it可以指代不可数名词吗?答:(2) It be adj. of sb. to do sth.此处adj. 通常为描述人的形容词:kind, unkind, nice, rude, cruel, considerate, thoughtful, thoughtless, careful, careless, silly, foolish, stupid, clever, wise, crazy.例 It‘s kind of you to help me with the problem.(3) It替代作主语的动...