YOU SAID:

the hamburger was eaten by clients, and then they left

INTO JAPANESE

ハンバーガーは客に食べられて帰ってしまいました

BACK INTO ENGLISH

The hamburger was eaten by the customer and left

INTO JAPANESE

ハンバーガーは客に食べられて帰ってしまった

BACK INTO ENGLISH

The hamburger was eaten by the customer and left