Oopellet
鲕球粒
🗣️ 情景例句
A clip-on?
用夹上去的？
I ought to go to bed now.
我应该现在去睡觉。
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。