The hit provokes that the curtain falls

It does not read like correct English, but could we have some more context please? It is hard to tell what you are talking about.

Dear GPY: First of all, thanks for your answer.

Charlie and Allan are two little boys playing in the room of Charlie. Suddenly Allan throws a heavy toy to the curtain. The hit of the heavy toy against the curtain provokes that the curtain falls.

Thanks for your time!!

No, it's not right. You can't provoke "that" something happens, and anyway "provokes" is the wrong verb (it can't really be used of inanimate things like curtains).

You could say "The impact caused the curtain to fall down". I added "down" because a curtain "falling" normally refers to the conclusion of a theatrical performance, or some related figurative sense, and this meaning seemed to

The hit of the heavy toy against the curtain caused the curtain to fall.

"Provoke" does not fit.

NikitusCharlie and Allan are two little boys playing in the room of Charlie. Suddenly Allan throws a heavy toy to the curtain. The hit of the heavy toy against the curtain provokes that the curtain falls.

I would tell the story like this:

Charlie was playing in his room with his friend Allan. Suddenly Allan threw a toy truck at the curtain, and the c