5.High School English Listening

If you want to fill a sink or bathtub with water, you need to do one thing first and that's stopper or plug up the drainpipe.
Later, when you unplug the stopper, the used water will go rushing out down the drain.
Hopefully, nothing valuable (such as a diamond ring) will be in that water, because after the water flows down the drain, it is gone forever.
Anything that was mistakenly dropped into the water will therefore also disappear down the drain, and then it will be very difficult probably impossible to get it back.
From the sad reality of losing a cherished object down a sink or bathtub drain comes this idiom, meaning to do or attempt to do something that ultimately will be lost forever.
It can also mean to put great effort into a wasted activity.
译文：
如果你想把水槽或浴缸装满水，你需要先做一件事，那就是塞住或堵住排水管。
稍后，当你拔掉塞子时，用过的水会顺着下水道冲出去。
希望这些水里没有什么有价值的东西（如钻戒），因为水顺着下水道流走后，它就永远消失了。
因此，任何被误掉进水里的东西也会顺着下水道消失，然后就很难或不可能再找回来。
这个成语来自于水槽或浴缸下水道丢失珍爱物品的悲惨现实，意思是做或试图做一件事，但最终将永远失去。
它也可以指为一项浪费的活动付出巨大的努力。
重点词汇：
want to 应该
and that 而且，并且
down the drain 破产;倒闭
such as 例如 ; 像 ; 象…这样 ; 诸如…之类
diamond ring 钻石戒指
and then 然后
be lost 迷 ; 失传