"I can't ride a horse for an hour."

Translation: 저는 한 시간 동안 말을 못 타요.

[TheSkunk]

Duolingo: 저는 한 시간 동안 말을 못 타요.
Me: 저는 한 시간 말을 못 타요.

What is the 동안 for?

저는 - I
한 - one
시간 - hour
동안 - ??
말을 - Horse
못 - can't
타요. - ride

I tried figuring it out with naver translate but the suggestions were "during" or "baby face" which didn't seem to fit.

Edit: Nevermind, I see now that it's "for"

[Clovita31]

Why is "한 시간 동안 저는 말을 못 타요" wrong?

[EEdLoh]

Probably just hasn't been made right yet by the devs? You should flag it?

[hotlagirl]

How do you know when to put the "for" into the sentence. I guess I can't tell where it should go when translating.

[david375511]

저는 말을 한 시간 동안 못 타요.