身體很虛弱；身體沒有力氣。
例句：
- Two months of illness left the athlete as weak as a kitten. (長達兩個月的臥病床榻，使得這位運動員的身體非常虛弱)
- Henry is as weak as a baby because he doesn’t eat well. (由於吃不下，亨利身體虛弱，沒有力氣)
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