Passive air defense
un. 消极防空
🧩 词语组成解析
air
[ɛə]
n. 天空;气氛;空运;（简单易记的）曲调;
vt.& vi. 晾晒;烘干;播送;广播;
vt. 使房间通风， 透气;
🗣️ 情景例句
Well, in 1919.
是的，在1919年。
'Tis altogether vain to learn wisdom and yet live foolishly.
枉自学聪明，却做愚蠢事。
Even if two of these were flooded, she would still be able to float.
即使有两个舱进水，仍可漂浮的水面上。