1
scum sth
宾语是被撇去浮渣的液体，不是浮渣本身。
You should scum the broth before adding the vegetables.
你应该在加入蔬菜前撇去肉汤表面的浮沫。
撇去（液体表面的）浮渣；撇沫
scums — third person singular of scum
先理解核心含义，再看它在真实句子里的用法。
撇去（液体表面的）浮渣；撇沫
To remove the scum from the surface of a liquid.
You should scum the broth before adding the vegetables.
你应该在加入蔬菜前撇去肉汤表面的浮沫。
撇去(液体等)表面的浮渣
To remove the layer of scum from (a liquid etc.).
将(某物)作为浮渣撇去
To remove (something) as scum.
布满浮渣
To become covered with scum.
撇去浮渣
remove the scum from
scum
Base
原形
scums
3rd person
第三人称单数
scumming
-ing
现在分词
scummed
Past
过去式
scummed
Past participle
过去分词
She scums the broth every morning.
她每天早晨撇去肉汤上的浮沫。
He scummed the soup before serving.
他在上汤前撇去了浮沫。
They have scummed the surface of the pond.
他们已经撇去了池塘表面的浮渣。
The chef is scumming the broth to remove impurities.
厨师正在撇去肉汤中的浮沫以去除杂质。
After boiling, she scummed the surface of the jam carefully.
煮沸后，她仔细地撇去了果酱表面的浮沫。
He always scums the soup before serving it to guests.
他总是在给客人上汤之前撇去浮沫。
宾语是被撇去浮渣的液体，不是浮渣本身。
You should scum the broth before adding the vegetables.
你应该在加入蔬菜前撇去肉汤表面的浮沫。
宾语是被撇去的物质，后接 off 和所在表面。
She scummed the fat off the sauce.
她把酱汁表面的油脂撇去。
不及物动词短语，表示表面逐渐布满浮渣。
The pond scummed over in the summer heat.
在夏天的炎热中，池塘表面结了一层浮渣。
Not this
He scumed the soup before serving.
Use this
He scummed the soup before serving.
动词 scum 以辅音字母 m 结尾，为重读闭音节，加 -ed 时应双写 m 得 scummed，不能写成 scumed。
Not this
She scummed off the foam from the stock.
Use this
She scummed the foam from the stock.
scum 作动词时是及物动词，可直接以浮渣作宾语，不需加 off；这里的 off 是从 skim off 类比误加，应删去。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
撇去浮沫
You should scum off the foam as soon as it rises to the top.
泡沫一浮到表面，你就应该把它撇去。
撇去汤里的浮沫
She scummed the soup with a ladle before serving it.
上汤前，她用长柄勺撇去了汤里的浮沫。
结上一层浮渣
The soup will scum over if you let it cool without stirring.
如果放凉时不去搅动，汤就会结上一层浮渣。
Use scums naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
记忆：/skʌm/ 像“似刮沫”，汤面浮沫叫 scum，用勺轻轻“刮”掉这层，动作就是动词 scum。
语域：formal 常见场景：cooking: removing scum from boiling broth or jam、industrial: skimming surface impurities from liquid in tanks、environmental: clearing scum from ponds or wastewater 作为动词，scum 多用于书面或技术性较强的语境，指撇去液体表面的浮渣或使表面结出浮渣；日常口语中更常说 skim (off) the scum，因此这里按正式用法标注。
及物动词，后接宾语
Dictionary facts from ECDICT, WIKTIONARY.