These new leather shoes don't fit me well. I now have an ugly shoe sore on my heel.
My new leather shoes don't fit me properly. There's a terrible blister on my heel now.
The new leather shoes I bought just don't fit me. There are sores on my feet now.
英訳１：fit ... wellで、「…がうまく合っていない」、shoe soreで「靴擦れ」という意味を表せます。on my heel「かかとに」とあるので、単に sore でも伝わります。
英訳２：properlyは、「適切に」という意味の副詞です。
blisterは「水ぶくれ、まめ」。
英訳３：There are ...「…がある」を使っています。
その他の言い方：
My new leather shoes don't fit me. There are sores on the soles of my feet now.
I'm not completely used to my new shoes yet, and it's caused some bad blisters on my heel.
My new shoes, which aren't completely broken in yet, have caused some bad blisters on my heel.
「(私の)靴になじむ」→「Get used to (my) shoes」
「かかと」→「Heel」
「靴擦れ」→「Blister」、靴擦れという単語は英語では単純に「水疱」といいます。
「I'm not completely used to my new shoes yet, and it's caused some bad blisters on my heel.」と
「My new shoes, which aren't completely broken in yet, have caused some bad blisters on my heel.」の二つの文は、どちらでも使えます。
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