YOU SAID:

the dog smells with its left nostril

INTO JAPANESE

犬は左の鼻孔で臭う

BACK INTO ENGLISH

The dog stinks in the left nostril.

INTO JAPANESE

その犬は左の鼻孔が臭い。

BACK INTO ENGLISH

The dog's left nostril stinks.

INTO JAPANESE

犬の左鼻孔が臭い。

BACK INTO ENGLISH

The dog's left nostril stinks.