成绩上下波动用英语怎么说

成绩上下波动通常用英语表达为"grade fluctuation"。这个说法源于"fluctuation"一词，它的意思是变化、波动。例句如下：

His grades showed a lot of fluctuation throughout the semester. (他在整个学期里成绩波动很大。)
The stock market is known for its fluctuations. (股市以波动著称。)
The temperature in the desert can fluctuate wildly. (沙漠里的温度会剧烈波动。)

希望这对您有帮助。