身体的免疫系统变得如此脆弱，以至于人们经常因为轻微的疾病而变得非常虚弱。

So weak does the body's immune system become that the person often becomes very ill from usually mild sicknesses.

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几乎所有的疾病都开始于缺乏营养和运动导致的脆弱的精神和虚弱的免疫系统。

A poor state of mind and poor immune system due to lack of good nutrition and lack of exercise.

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