Phase velocity
[化] 相速
🧩 词语组成解析
🗣️ 情景例句
Yes, we are surprised to meet you here.
是的，我们意外在这儿见到了你。
Good to begin well, better to end well.
善始好，善终更好。
I like reading English books, but they're sometimes rather hard.
我喜欢看英语书，但有时候英语书相当难读。