it可以指代不可数名词吗?答:1. 代作主语的动词不定式,其句型为 (1) It be adj. (for sb.) to do sth.此处adj. 通常为描述事件的形容词:easy, difficult, hard, necessary, unnecessary, possible, impossible, likely, unlikely, right, wrong, important, unimportant, legal, illegal, well-mannered, ill-mannered, ...