Ultravacuum
超真空
🗣️ 情景例句
Especially when it comes to speaking in English and fortunately or unfortunately.
特别是要用英文来演讲，不知是幸运还是不幸。
I wonder what he's doing.
我不知道他在做什么。
It's no use complaining.
发牢骚没什么用。