I thought his fever had finally broke and then I saw that he had broken out in a rash.
My son's temperature had finally dropped and then I noticed he had a rash on his body.
ー I thought his fever had finally broke and then I saw that he had broken out in a rash.
「やっと息子の熱が下がったと思ったら、発疹が出てきた。」
one's fever had finally broke 「熱がやっと下がった」
break out in a rash「発疹が出る・ブツブツが出る」
ー My son's temperature had finally dropped and then I noticed he had a rash on his body.
「息子の熱がやっと下がったら、体に発疹が出ているのに気がついた。」
one's temperature had finally dropped 「熱がやっと下がった」
have a rash on ...「…に発疹が出る」
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カナダ 
