Hold it vertically at the beginning, and you can't enter; Hold it horizontally, but you can't enter it. What does this sentence mean?

Hold it vertically at the beginning, and don't

enter it; Hold it horizontally, but you can't go in. What does this sentence mean?

This sentence is from Holding a Pole into the City. If you can, you can add another sentence: "Why not cut it off in a play?

" At first, you can't hold it vertically, you can't enter it horizontally, you can't enter it, you can't count it out. "

Start holding a bamboo pole vertically.

"Why not cut in a play?"

why don't you take it from the middle?