Watermarks
n. 水印( watermark的复数形式 )
🗣️ 情景例句
What was the weather like yesterday?
昨天的天气怎么样？
To play with his son
和儿子玩耍
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。