塞上的英文：
【机】 blank off

参考例句：

Plug stopcocks with sterile plugs
在三通开关上塞上无菌塞子。

The piston end of the rod is attached to the piston by the piston pin, or wrist pin
连杆的活塞端用活塞销或销轴安装在活塞上。

Of course, this doesn't mean you should shove a clove of garlic into your ear and hope for the best.
当然，这不代表你往耳朵里塞上大蒜瓣就完事大吉。

So if you fill your sink up, but leave the plug out, when the water level stops rising, the water in = the water out.
比如你往洗手池里灌水却没把塞子塞上，当水位停止上升的时候，就可以说，流进的水=流出的水。

off是什么意思：
adv. 掉，下；离开；隔开；切断；停止；；休息；光，完，尽；全部地
prep. 从...离开；从...向下；在...的外面；偏离...；从...分岔；不再从事...；低于...
adj. 关着的；停止流通的；延期的；取消的；不工作的；处于...境况的；萧条的
v.（用于祈使句）走开，滚开；站开
n. 关掉

Is the water on or off?
自来水龙头开着还是关着？

The gilt is off.
幻想破灭了。

to nip off; to cut off; to break
掐断

take off clearance = clearance for take off
起飞许可

They panned off the sand and dirt.
他们用淘金盘淘去砂泥。