It's important后面是接-ing还是接to do?

to do

减少人工关节的并发症十分重要
It is important to diminish complications in arthroplasty

It is important to choose the optimization control function.
耗能器优化设置问题的关键在于控制函数的选取。
It is very important to foster English reading ability.
英语阅读能力的培养非常重要。

It is Important to Train Spoken Ability in Chinese Teaching
语文教学不可谈化口头能力的培养

improtant + doing sth.

to do 拉
你应该还是刚刚那个出题的人吧

improtant to do sth.

to do

to do