"Don't walk around with a spoon in your mouth"
A self explanatory statement, if you do you will likely hurt yourself.
"Don't run around with a spoon in your mouth" etc..
"Take that out your mouth when walking"
'Take out' is referenced to remove something, in this case a spoon out the mouth.
"Don't walk around with a spoon in your mouth"（スプーンをくわえて歩かないで）
は、非常に分かりやすい文です。スプーンをくわえて歩くとけがをしてしまうかもしれません。
"Don't run around with a spoon in your mouth"（スプーンをくわえて走り回らないで）
"Take that out your mouth when walking"（歩くときはそれを口から出して）
'Take out' は「～を取り除く」という意味です。ここでは、「口からスプーンを」ということです。
Children are always on the go and rushing around and can easily fall over so having a spoon in their mouth can be dangerous as it might get stuck so you would want to tell them not to walk around with a spoon in their mouth
Don’t walk with a spoon in your mouth.
(スプーンを咥えながら、歩かないで)。
Don’t walk around with a spoon in your mouth.
(スプーンを咥えながら、うろちょろしないで)。
Don’t run around with a spoon in your mouth.
(スプーンを咥えながら、走り回らないで)。
It’s very dangerous.
(とても危ないよ)。
Please sit down and eat.
(座って、食べてください)。
参考までに！
Don't walk with a spoon in your mouth or you will get an owie.
Sit down when using a spoon.
Please put the spoon down before you walk around.
Don't walk with a spoon in your mouth or you will get an owie. (An owie is an injury. Small children understand when they get hurt they say "ow" so we call it an "owie".
Sit down when using a spoon.
You need to sit down when you have a spoon in your mouth.
That's not a good idea to walk around with a spoon in your mouth.
Please go sit at the table until you are done eating. Then you can get up.
Don't do that! Don't walk around with a spoon in your mouth!
Please put the spoon down before you walk around.（スプーンをくわえたまま歩かないで）
Don't walk with a spoon in your mouth or you will get an owie.（スプーンをくわえたまま歩いちゃダメ。けがするよ）
※ "owie" とは（幼児語で）「けが」のことです。小さな子どもでもけがをすると "ow" と言うことは分かるので、"owie" と言います。
Sit down when using a spoon.（スプーンを使うときは座りなさい）
You need to sit down when you have a spoon in your mouth.（スプーンを使うときは座りなさい）
That's not a good idea to walk around with a spoon in your mouth.（スプーンをくわえたまま歩くのは良くないよ）
Please go sit at the table until you are done eating. Then you can get up.（食べ終わるまではテーブルで座っていなさい。食べ終われば、立ち上がってもいい）
Don't do that! Don't walk around with a spoon in your mouth!（やめなさい。スプーンをくわえたまま歩いたらダメ）
It's dangerous to walk with a spoon in your mouth!
You can hurt yourself walking around with a spoon in your mouth!
It is unsafe for you to walk with a spoon in your mouth!
It is difficult being a parent because our children don't always believe what we tell them, especially about the dangers of doing certain things.
It's dangerous to walk with a spoon in your mouth!
"dangerous" - something that can cause us harm or an injury
You can hurt yourself walking around with a spoon in your mouth!
It is unsafe for you to walk with a spoon in your mouth!
子育ては大変ですね。子どもは言うことを聞いてくれないときがあります、特にやっては危険なことについて。
It's dangerous to walk with a spoon in your mouth!（スプーンをくわたまま歩いたら危ない）
"dangerous" - 人に害を与えたり、あるいはけがを引き起こす可能性のあるもの。
You can hurt yourself walking around with a spoon in your mouth!（スプーンをくわたまま歩いていたら、けがすることだってあるよ）
It is unsafe for you to walk with a spoon in your mouth!（スプーンをくわたまま歩いたら危ない）
一番シンプルな言い方は Don’t walk with a spoon in your mouth.
Don’t＝～しないで
walk=歩く
with=～と一緒に
a spoon=スプーン
in your mouth=あなたの口の中
食事のシーンで合わせて使えそうな文章もご紹介します。
Hold this tight. (しっかり持って！）
Just one more bite! (あと一口！）
Go ahead and finish it up. （全部食べちゃおう！）
Are you full? (おかないっぱい？）
Are you done? (もうおしまい？）
少しでも参考になれば幸いです。
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