it's+adj+for+sb. to do sth 做某事对某人来说...
it's+adj+of+sb. to do sth做某事对某人来说....
it's+take/took+sb+time to do sth 某人花费时间做某事
it's+useless/no use+doing sth 做某事是没有好处的
it's+no good+doing sth 做某事是没有好处的
it's a waste of time dong sth 做某事是浪费时间的
it's said/report/important/necessary/no wonder/an honor/a pity that+句子