Crossing the river joke

Connotation paragraph: There is a man taking a bath in the river. Guess whether it's a man or a woman.

One day, a blind man crossed the river with a cripple on his back. A man is taking a bath in the river. At this moment, the lame man said, "There is a man taking a bath in the river. Guess whether it is a man or a woman. " The blind man said, "Woman." The lame man said, "How do you know when you are lying in the trough?" The blind man said, "My waist is tied, Lao Tie."