In Europe, though, aircraft were often flown in different countries, and it soon became apparent that some kind of standard rules were needed.

而在欧洲，飞机经常在各国之间穿梭飞行，很快有人意识到，是应该建立某些规则了。

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We want to know some data (performance) of this kind of aircraft, such as.

我们相了解这种飞机的一些数据，比如。

youdao

We want to know some data (performance) of this kind of aircraft, such as.

我们相了解这种飞机的一些数据，比如。

youdao