YOU SAID:

Hello, I would like a slice of Pepperoni Pizza.

INTO JAPANESE

こんにちは、ペパロニピザを一切れ欲しいのですが。

BACK INTO ENGLISH

Hi, I'd like a slice of pepperoni pizza.

INTO JAPANESE

こんにちは、ペパロニピザを一切れください。

BACK INTO ENGLISH

Hi, I'd like a slice of pepperoni pizza.