人类好不容易才发明了能飞行的器具——飞机。飞机开始只能平飞和转弯,后来逐步发展了多种飞行特技。可以这样说,现在飞机所做的某些特技飞行动作连飞鸟也从来没有做过。也许不是飞鸟不能做,而只是它们认为没有必要这样“飞”。 Human beings finally invented a flying appliance - the plane. The plane began to fly and turn only flat, then gradually developed a variety of flight stunts. It can be said that some aerobatics now performed by the aircraft have not even been done by birds. It may not be that the birds can not do it, but only they do not think it necessary to “fly.”