When the waiter asks if you want to order anything else, but you're full, you can say:
"No thanks, I'm full."
"I'm already full, but thanks for asking."
以下は、ウエイターが追加注文をしたいか聞きにきて、もうお腹がいっぱいであることを伝えるフレーズです。
"No thanks, I'm full."
（いいえ結構です。お腹いっぱいです。）
"I'm already full, but thanks for asking."
（もうお腹いっぱいです。ありがとうございます。）
All the sentences are clear and can be used in this situation.
Example
Brother: Would you like some more meat?
Me: No thank you, I had enough.
Brother: Are you sure? Just a small piece.
Me: I don't think I can anymore.
Brother: Okay, but you are welcome to have more.
Me: I am very full thank you.
上記のすべての文章はとてもはっきりしており、この状況で使用することができます。
例文
Brother: Would you like some more meat?
兄：もう少し食べたい？
Me: No thank you, I had enough.
私：ありがとう、十分だよ。
Brother: Are you sure? Just a small piece.
兄：本当？ 少しでも？
Me: I don't think I can anymore.
私：もう食べれないと思う
Brother: Okay, but you are welcome to have more.
兄：オッケー、もっと食べたいだったら全然いいからね。
Me: I am very full thank you.
私：もうお腹いっぱい。ありがとう
"Thank you but I am full." and "No thank you ,I am stuffed." are ways to thank the waiter/waitress for the offer and explain that you are quite satisfied and are thus unable to eat more.To be "stuffed " is the same as saying you are " full" as they both mean you can't have any more food.
"Thanks but I couldn't possibly eat more."
This means that you are physically unable to eat any more food as you may have eaten too much already.
You also say "I don't think I can eat anymore." and the waiter will understand that you are full and will not be ordering more food.
"Thank you but I am full." ありがとう、でももうおなかいっぱいです。"No thank you ,I am stuffed." 結構です。もうおなかパンパンです。はウェイターやウェイトレスに聞いてくれたことに感謝してもう満腹だと説明することで食べられないと伝えます。 "stuffed " と" full"は同じ意味で満腹でもう食べられないという意味です。
"Thanks but I couldn't possibly eat more."ありがとう、でももう食べられそうにありません。
もう食べ過ぎでこれ以上食べられないという意味です。
"I don't think I can eat anymore."これ以上食べれるとは思いません。という表現も、ウェイターはこれ以上オーダーはしないなと理解します。
Thank you, but I can't have another bite.
I can't have another bite is an informal or casual
way of telling the person that you are so full that
you cannot possibly eat any more.
I've had my fill, thanks.
This means that the meal has satisfied you and
that you are too full to eat anything more.
Thank you, but I can't have another bite.
（ありがとうございます。でももうお腹いっぱいです。）
I can't have another bite は、お腹がいっぱいでもう食べられないことを意味するカジュアルな表現です。
I've had my fill, thanks.
（お腹いっぱいです。ありがとうございます。）
これは、満足のいく食事ができて、お腹がいっぱいなのでもう食べられないという意味です。
If you have had enough to eat and would like to express that to the waiter or your mate, you can use the sentences above.
When you feel full, eating doesn't feel so great anymore.
"No thank you, I've had enough." is telling the server that you do not want to order anything else from the menu because you are full and you have had enough to eat and drink.
"No thank you, I've had enough."（結構です、もう十分いただきました）
は、「もうお腹がいっぱいで注文したいものはない」と伝えます。
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