YOU SAID:

The back of the horse is getting itchy

INTO JAPANESE

馬の背中が痒い

BACK INTO ENGLISH

Horse's back is itchy

INTO JAPANESE

馬の背中がかゆい

BACK INTO ENGLISH

My horse's back is itchy.

INTO JAPANESE

私の馬の背中がかゆいです。

BACK INTO ENGLISH

My horse's back is itchy.