It has a huge mast, with the mainsail attached.

它有一个巨大桅杆，主帆附着上面。

This one here is called the main sail.

这个在这里被称为主帆。

How do you get the mainsail up? Uh...

要怎么把主帆升上去。

So they literally windsurf off the wind that comes off the mainsail and they hang.

所以他们利用主帆吹风帆冲浪，挂起。

You can control this main sail, whether it's close or far out, and to have that just in the right place will affect the speed of the boat.

你可以控制这个主帆， 无论它靠近还远离，把它放在正确位置会影响船速度。

I was very much tired, and disposed to sleep, which my mistress perceiving, she put me on her own bed, and covered me with a clean white handkerchief, but larger and coarser than the mainsail of a man-of-war.

我非常疲倦，准备睡觉，女主人看出了这一点，她把我放在她自己床上，并用一块干净白手帕盖在我身上，但比军舰主帆更大更粗糙。