「Careful, it's hot.」（「熱いよ。気をつけて。」）
もしくは
「Try not to burn your tongue.」（「舌をやけどしないようにね。」）
が定番のフレーズになります。
※後者について、「口」というよりも、なぜか「舌」の方をよく耳にしますので、
「tongue」という単語を使用しています。
You may want to let that cool down a bit. It's piping hot!
...really + adjective = we use this expression when we want to stress the adjective in our phrase.
My god, it's really hot today = very hot
may piping hot = (of food or water) very hot.
"The crust was piping hot"
To cool down = cool down - make cool or cooler; "Chill the food" = "Cool down the food.
...really + adjective =この文法は形容詞を強調したいときに使います。
My god, it's really hot today = very hot すごく熱い
may Piping hot = (of food or water) very hot. 食べ物や飲み物が非常に熱い
"The crust was piping hot" 生地がすっごく熱い
To cool down = cool down - 熱を下げること "Chill the food" = 食べ物を冷ますこと。
Be careful! The food is hot and will burn your mouth.
Don't burn yourself! The food is still piping hot. Be careful.
Hang ten for a few seconds. the food will scald your mouth. Let it cool down firts.
We normally say something is still piping hot - meaning it is very hot and could burn one's mouth or
any body part.
best to warn somebody as piping hot food will scald or burn the mouth.
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