Indexometer
[医] 折射指数计
🗣️ 情景例句
I've been moonlighting for years.
我几年来一直兼职。
Quality matters more than quanity.
质量比数量重要。
It is the natural frequency of emission of the hydrogen atoms in space and was discovered by us in 1951;
这个频率是空间氢原子释放的自然频率，是在1951年被人类发现的。