drop by drop

基本解释

A can for oil, especially a can with a spout constructed to release oil drop by drop, as for lubricating machinery.
油罐盛油的罐，特别是指安着可一滴一滴地滴油的喷嘴的油罐，用以润滑机器。
in villages, the new pipeline marks the end of water as a precious liquid, to be dispensed frugally, weighed out drop by drop.
在农村，新的输水管道标志着水作为一种珍贵液体的年代的结束，水可以节省地分配到各处，可以一滴一滴地称量。
Drip, or “micro, ” irrigation, as the name suggests, is stingier with the water, delivering it to the roots of plants drop by drop.
正如名字所暗示的，滴灌，或者微灌注技术则要抠门的多，它们一滴一滴地把水滴到植物的根部。

Just last week,the Commerce Department reported an unexpected drop in December in the number of housing starts by builders.
So, it's a trivial matter, by looking at what is the weight and how far does it drop, to say OK, how much work is done by the paddle wheel.
好，让我们看看重物的质量,以及它下落的距离，就知道桨轮做了多少功。
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because there are a lot of stars that live around here that sometimes drop by.
因为这附近住着很多明星，他们有时候会路过。
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As in filling a vessel drop by drop, there is at last a drop that makes it run over.
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