Permatron
[计] 磁控管
🗣️ 情景例句
This time draft will fall due at the end of this year.
这张期票年底到期。
That's why he is now concentrating on conversation at a language school near his home.
这就是他在他家附近的一所语言学校专攻口语的原因。
He came out of the library, a large book under his arm.
他夹着本厚书，走出了图书馆。