Donutron
笼圈式谐振腔磁控管
🗣️ 情景例句
Are you from Taiwan?
您是从台湾来的吗？
I asked him to do it for me, but he wouldn't.
我请他帮我做，但是他不肯。
It can be unpleasant to live even several miles from an aerodrome;
即使住在离机场几英里以外的地方，机场的噪音也会使人难受。