YOU SAID:

I should get sushi for dinner

INTO JAPANESE

私は夕食に寿司を取るべきです

BACK INTO ENGLISH

I should have sushi for dinner

INTO JAPANESE

私は夕食に寿司を食べるべきでした

BACK INTO ENGLISH

I should have had sushi for dinner.

INTO JAPANESE

私は夕食に寿司を食べるべきだった。

BACK INTO ENGLISH

I should have eaten sushi at dinner.

INTO JAPANESE

私は夕食で寿司を食べるべきだった。

BACK INTO ENGLISH

I should have eaten sushi at dinner.