病弱

例句：

1. 1. The old man is very weak andneeds to rest more.
   老人非常虚弱，需要休息更多。
2. 2. She was so sicklythat she couldn't even walk.
   她病得很重，甚至不能走路。
3. 3. Thebaby is weak and needs to be fedfrequently.
   婴儿很虚弱，需要经常喂食。