Background impurity
[化] 本底杂质
🧩 词语组成解析
🗣️ 情景例句
and we should remove them as soon as possible.
我们要尽快把它切除。
I only need a thousand more pennies to buy my airplane.
我只要在有一千个一角的铜板，就能买一架飞机了。
As the parents had five children, life was a perpetual struggle against poverty.
家里已有5个孩子，全家人常年在贫困中挣扎。