Concentration fluctuation
[建] 浓度升落
🧩 词语组成解析
fluctuation
[,flʌktʃʊ'eʃən]
n. 波动，涨落，起伏，[物]脉动;动摇不定，踌躇;[生]彷徨变异;
fluctu 波浪 + ation 表示行为、情况、状态、过程、结果 → n.波动, 起伏
🗣️ 情景例句
It's the world's largest island, but it's also the world's smallest continent.
它是世界上最大的岛屿，同时也是世界上最小的洲。
The mother's heart is the child's schoolroom.
母亲的心肠是孩子的课堂。
What was the population of the world in 1950?
1950年世界人口是多少？