C4
abbr. 补体4（complement 4）
🗣️ 情景例句
You were right, Robbie.
你做对了， Robbie。
Why did you sit up so late?
为什么你这么晚还不睡觉？
It's to the north of England; it's part of Britain.
它位于苏格兰的北部，是不列颠的一部分。