air tightness

例句：

1. 1. The new air-conditioner has a very high air tightness.
   这款新型空调的密封性非常高。
2. 2.The door was sealed tightly to prevent any leakage.
   门被紧紧地封住以防止任何泄漏。
3. 3. The sealing quality of the new product is superior to that of the old one.
   新产品的密封质量优于旧产品。