双语例句
The level of carbon dioxide in the atmosphere is measured in parts per million (ppm).
大气层里二氧化碳含量的测量单位是ppm，即一百万体积的空气中所含二氧化碳的体积数。
词典释义：
parts per million (ppm)
时间: 2026-01-22 02:41:36
百万分率(ppm)
词典释义：
百万分率(ppm)
The level of carbon dioxide in the atmosphere is measured in parts per million (ppm).
大气层里二氧化碳含量的测量单位是ppm，即一百万体积的空气中所含二氧化碳的体积数。