Radiotron
真空管, 三极电子管
🗣️ 情景例句
Don't worry, it's in the bag.
不用担心， 这事儿十拿九稳。
He's concentrating on learning English.
他集中精力学英语。
one ought to have at least two or three hobbies, and they must all be real.
至少应有两三种爱好，而且都比较实际。