Underair
大气最下层
🗣️ 情景例句
Yes.
是的。
Don't forget to put stamps on the letter before you mail it.
不要忘记在寄信以前把邮票贴在信封上。
it was not long before its use as the uniquely recognizable broadcasting frequency for interstellar communication was suggested.
提出把它作为星际间唯一可辨认的广播频率就为期不远了。