阅读疑问1为什么第一段所对应的是
全段原文如下：
THE FIRST AEROPLANES
[What were the difficulties which the early pioneers had to overcome in making successful aeroplanes?] One of the difficulties was to decide what general system ought to be used。 Naturally the first idea was to use wings as birds do, and some men actually provided th...全部
全段原文如下：
THE FIRST AEROPLANES
[What were the difficulties which the early pioneers had to overcome in making successful aeroplanes?] One of the difficulties was to decide what general system ought to be used。
Naturally the first idea was to use wings as birds do, and some men actually provided themselves with wings fastened to their arms; but they failed。
It is an interesting fact that when men try to do the same things as nature does, they usually have to do them in a different way。
Carriages, trains and motorcars use wheels instead of legs; aeroplanes have fixed wings, unlike those of birds; boats are moved by oars or by the wind, and ships by paddle-wheels or screws, though not one of these methods is used by any fish。
In general, too, the wheel, a necessary part of most machines, never appears in nature。 Thus the decision to use a fixed wing was one that had to be made before any aeroplane could fly satisfactorily。
Some of the early machines had a lot of wings of various sizes and in different positions。 The number was soon reduced to a maximum of three, one above the other。
The machine with three wings was known as a triplane; it disappeared from the sky long ago。 The biplane, with two wings, lasted longer and could be seen fairly frequently up to the war of 1939, though it is now becoming a rarity。
The monoplane is now the commonest type of aircraft。 It has the advantage that it presents less resistance to the air than other types, and can therefore fly faster with the same power。
相信第一段的答案不该是A。 The triplane (三翼飞机) is still in use nowadays，因为第一段的内容只涉及制造飞机的基本理念—to decide what general system ought to be used及Thus the decision to use a fixed wing，只决定了飞机该有翼，还未决定翼的数目。
在六个选择中，觉得B。 Man had tried hard to fly an air machine。 比较适合，因为这一段的重点就是漏掉了的第一句—What were the difficulties which the early pioneers had to overcome in making successful aeroplanes?。
第二段的重点在于介绍不同型的飞机，有triplane, biplane, monoplane，所以不难理解应该选 E。 There are different types of air machine。
在做英语阅读理解的其中一??窍门是了解一篇文章的主干，在每段的首句或者最后一句，了解这段文章的主要大意。收起
