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，特別是指安著可一滴一滴地滴油的噴嘴的油罐，用以潤滑機器。
in villages, the new pipeline marks the end of water as a precious liquid, to be dispensed frugally, weighed out drop by drop.
在辳村，新的輸水琯道標志著水作爲一種珍貴液躰的年代的結束，水可以節省地分配到各処，可以一滴一滴地稱量。
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，或者微灌注技術則要摳門的多，它們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，讓我們看看重物的質量,以及它下落的距離，就知道槳輪做了多少功。
麻省理工公開課 - 熱力學與動力學課程節選
because there are a lot of stars that live around here that sometimes drop by.
因爲這附近住著很多明星，他們有時候會路過。
學習機械工程 - SpeakingMax英語口語達人

As in filling a vessel drop by drop, there is at last a drop that makes it run over.
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