YOU SAID:

I have never eaten a donut

INTO JAPANESE

ドーナツを食べたことがないです。

BACK INTO ENGLISH

There is no eating donuts.

INTO JAPANESE

食べるドーナツはありません。

BACK INTO ENGLISH

Don't eat donuts.

INTO JAPANESE

ドーナツを食べてはいけない。

BACK INTO ENGLISH

Don't eat donuts.