it is adj to do sth和it is adj doing sth

哎,不知道为什么上面的人都说it`s a.doing是错的,明明是对的嘛It is + no use,no good (fun,a great pleasure,a waste of time,a bore...)等名词+doing sth.It is no use crying.哭没有用.It is no good objecting.反对也没有用.It is a great fun playing football．打篮球很有趣.It is a waste of time trying to explain．设法解释是浪费时间.It is + useless (nice,good,interesting,expensive等形容词)+ doing sth． It is useless speaking.光说没用.It is nice seeing you again．真高兴又遇到了你.It is good playing chess after supper．晚饭后弈棋挺好.It is expensive running this car．开这种小车是浪费.

后面一个是错误的

to do sth 错的只有It's +adj+(for sb)+doing sth这是基本！！！

没区别