have problem（in） doing sth 中的（in） doing sth 作什么句子成分

have problem（in） doing sth 中的（in） doing sth 作什么句子成分 have problems in doing sth 和have a problem in doing sth have difficulty in doing sth .have trouble in doing sth 到底是have a problem in doing sth have trouble in doing sth have confidence in doing sth have difficulty in doing sth 1.是have problem (in) doing sth.还是have problems (in) doing st have no problems (in) doing sth.中的problem永远都加s吗? can't help doing sth.have confidence in doing sth have difficulty还是difficultyies （in）doing sth? "HAVE FUN DOING STH" 和" HAVE IN DOING STH " 有什么区别?,可以通用吗?