I gave it a roof but it ended up taking the room as its own.
One night, I let my dog sleep in my room because it was scared of thunder. It was only supposed to be for that day, but before I knew it the dog ended up mistaking the room as its own. I gave it a roof but it ended up taking the room as its own.
ご質問ありがとうございます。
この場合は、直訳できないですが、近い意味で「I gave it a roof but it ended up taking the room as its own.」という風に言えます。
また、「ある夜 飼い犬が雷を怖がったので、その日だけわたしの寝室に入れ一緒に寝たら、いつのまにかわたしの寝室を自分の部屋だと勘違いしているよう。」という説明の英訳も知りたい場合、「One night, I let my dog sleep in my room because it was scared of thunder. It was only supposed to be for that day, but before I knew it the dog ended up mistaking the room as its own. I gave it a roof but it ended up taking the room as its own.」になります。
ご参考になれば幸いです。
これを英語で表現する場合、"Give them an inch, and they'll take a mile."がよく使われます。このフレーズは、少し許したらそれ以上に心配なことが起こるという意味です。
質問補足の例について言えば：
"I let my dog sleep in my room just once because he was afraid of thunder, and now he thinks it's his room. It's like giving an inch and losing a mile."
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