When the pull line is pulled or loosened, the reel can rotate positively and reversely, which drives the screen curtain to roll up or fall down.

拉动或松开拉线，卷筒可正、反向转动，带动纱帘卷起或落下。

youdao

So if you've ever seen or used an old school typewriter, you might recall that when you're typing something out on an old mechanical typewriter, - when you like hit the char-- when you hit the enter key to move the head back to the left hand side to the next line or you would pull down some lever, it was really a two part process.

如果你们有谁曾经看过或用过老式打字机，可能还记得，当你在,这种老式打字机上打字的时候，当你-,敲入回车键，跳转到,下一行的最左边，或者,拉一下杆，这个需要两步走。

哈佛公开课 - 计算机科学课程节选

Sharks are smooth, steady swimmers, so the pull on the line was constant and heavy rather than the spastic tugging that I have experienced from other fish.

WSJ: Fishing for Shark in Destin, Fla.

That was when Mariano Rivera took it upon himself to pull Nova back into line.

WSJ: Yankees: How Mariano Rivera Set Ivan Nova Straight

The crew tried to pull it in, hand over hand, but each pull seemed to edge the line closer to the propeller.

NEWYORKER: Neptune��s Navy