YOU SAID:

i like horsebackriding i am doing it for 8,5 years now

INTO JAPANESE

私は乗馬が好きで、8,5年間乗っています

BACK INTO ENGLISH

I like horseback riding and have been riding for 8 or 5 years

INTO JAPANESE

乗馬が好きで、8、5年乗っている。

BACK INTO ENGLISH

I like horseback riding and have been riding for eight or five years.

INTO JAPANESE

私は乗馬が好きで、８、５年乗っています。

BACK INTO ENGLISH

I like horseback riding and have been riding for eight or five years.