他们发现他身体半裸，流着血，快不行了。

They found him half naked and bleeding to death.

《牛津词典》

当我走开的时候，女孩的父亲抓住了我的胳膊，我转过身，他说道：“我女儿可能快不行了。”

As I walked away, her father grabbed my arm and turned me around, saying, my little girl is probably not going to make it.

youdao

他认为他能和他朋友走得一样快，但他不行。

He thought he could walk as quickly as his friend, but couldn't.

youdao