美国航空自1991年开始已经成为美国最大的航空公司，和别的航空相比，美国航空公司在很多领域都是先锋，很具有竞争力和优势。

American airlines is the biggest airline in the United States since 1991. American airlines was pioneer in many fields gaining competitive and advantage over the other airlines.

youdao

美国航空自1991年开始已经成为美国最大的航空公司，和别的航空相比，美国航空公司在很多领域都是先锋，很具有竞争力和优势。

American airlines is the biggest airline in the United States since 1991. American airlines was pioneer in many fields gaining competitive and advantage over the other airlines.

youdao