Air tightness
[機] 氣密度
?? 詞語組成解析
air
[??]
n. 天空;氣氛;空運;（簡單易記的）曲調;
vt.& vi. 晾曬;烘干;播送;廣播;
vt. 使房間通風， 透氣;
n. 堅固, 緊密\\n[化] 緊度; 嚴密度
??? 情景例句
It's eleven thirty.
十一 點半。
Hiking gives you time to think.
郊游可以使你有時間思考。
It must have been about two in the morning when I returned home.
我回到家時，肯定已是凌晨兩點左右了。