1.The police verified that she had an airtight alibi.

1.警方查明她有着无懈可击不在犯罪现场。

2.Biscuits will stay crisp if you keep them in an airtight tin.

2.如果你把饼干放到一个密闭铁罐里, 它就会保持松脆。

3.Applicable to acid (except vaporish acid),alkali, ammonia, vapor, oil, organic solvent ,chemistry corrosiveness, filling airtight of rotary pump.

3.适用酸（除烟硫酸外）碱，，氨，蒸气，油品，有机溶剂，化学腐蚀性介质各种旋转泵，填料密封。

4.The article introduces a fire autoalarm which can be used in large airtight oil depot or fuel storehouse.

4.摘要文章提出了一种大型密闭油库，密闭燃油机房等场所用到火灾自动报警装置。