What counts most is quality.最重要的是质量.这句话不能用which 哈 which是用于多个选择的时候 单纯的表达一个事物的时候用what比如：What matters is honesty.诚实不诚实是介意的What I like is playing football....感谢您的答案能举个适用于由which引导的主语从句吗？Which way to go is a problem.Which car should I buy is not decided.Which one runs most quickly is going to winthis game.