question problem matter trouble bother worry 哪些有复数形式

question problem matter trouble bother worry 哪些有复数形式 trouble matter problem question trouble problem question matter 的区别 problem,trouble,matter,question的区别 trouble,problem,question有什么区别 problem question trouble? question problem trouble wrong 区别 question有没有复数形式 MATTER,QUESTION,PROBLEM怎么区别 problem和matter和question有什么不同? problem.question,trouble,difficulty的区别? difficulty,problem,trouble,question的区别