We use this expression when we cannot understand something we read or hear.
当我们不理解看到的或听到的某件事时，可以使用这句表达。
We cannot understand disease unless we understand the person who has the disease.
除非我们了解有某种疾病的人，否则我们不会了解疾病。
We cannot understand disease unless we understand the person who has the disease.
除非我们了解有某种疾病的人，否则我们不会了解疾病。
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