healthy的对应词是：disease

n.病;疾病;弊端;恶疾;痼疾

复数： diseases

例句：

Extensive research has been done into this disease.

对这种疾病已进行了广泛研究。

According to official statistics the disease killed over 500 people.

根据官方的统计数字，500多人死于这种疾病。

Smoking can increase the risk of developing heart disease.

吸烟会增加得心脏病的危险。

In an ideal world there would be no poverty and disease.

在理想的世界里将没有贫穷和疾病。