为什么飞行？

为什么飞行？因为一旦你已经试过飞行，你会用你转向天空的眼睛行走地球，因为你曾经去过，而你渴望再次回到那里。

Leonardo Da Vinci : Why fly ? For once you have tested flight, you will walk the earth with your eyes turned skyward, for there you have been, and there you long to return.