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thank you (for the meal); that was a delicious meal
thank you (for displaying lovey-dovey behaviour)
御馳走様でしたとても美味しかったです。
Thank you for the meal, it was very delicious.
食事の後は御馳走様と言いましょう。
Let's say 'gochisousama' after eating.
レストランを出る時に御馳走様と言った。
I said 'gochisousama' when leaving the restaurant.