我认为有必要英语

i think it's neccessary to teach children with the homework!

(It's) (necessary) (to) tell the thing to him.如果非要是三个空,我想应该只能这样了吧.省略掉"I think".全句应该是I think it is necessary to tell the thing to him.

I think it's necessary to teach children how to do housework.

是think it necessary阿,因为那个to跑到后面去仂--thing to him.

可以用I think you should tell the thing to him认为你应该（必须）把那件事告诉他的意思