USAGE NOTE 用法说明: disease, illness, sickness
Although disease and illness are often used to mean the same thing, it is the disease that actually makes you ill. 虽然 disease 和 illness 常用来表示同一回事〔生病〕，但实际上导致生病的原因却是 disease:
He suffers from heart disease. 他患有心脏病。
An illness is the condition of being ill, which may be caused by a disease. illness 用于表示生病的状态，它可能是由 disease〔疾病〕引起的:
She missed a lot of school because of her illness. 她因病漏掉了许多课。
Sickness is a particular type of illness. sickness 是某种特定的疾病或生病状态:
radiation sickness 放射性疾病
travel sickness 晕车［船、飞机］