YOU SAID:
I bought some mangoes
INTO JAPANESE
マンゴー買ってきた
BACK INTO ENGLISH
i bought a mango
INTO JAPANESE
マンゴーを買いました
BACK INTO ENGLISH
bought a mango
INTO JAPANESE
マンゴーを買いました
BACK INTO ENGLISH
bought a mango
That didn't even make that much sense in English.