Question

Bendable wings covered with overlapping (重叠部分) pieces looking like fish scales could be used to build more controllable, fuel­efficient aircraft, a new study finds.

Nowadays, conventional aircraft typically rely on ailerons (副翼) to help control the way the planes tilt (倾斜) as they fly. However, when the Wright brothers flew the first airplane, Flyer 1, over a century ago, they used no ailerons but wires that pulled and stretched the wood­and­canvas wings, to control the plane.

“Scientists have long sought to develop aircraft that can change their wings during flight, just as birds can. However, most previous attempts have failed because they relied on heavy mechanical control structures within the wings. These structures were also complex and unreliable，” said Neil Gershenfeld, a physicist and director of the Centre for Bits and Atoms at MIT.

The new wing consists of a system of tiny, strong and lightweight modules (组件). The shape of the wing can be changed uniformly along its length using two small motors, which apply a twisting pressure to each wingtip. These wings are covered in “skins” of overlapping strips of flexible material like fish scales. These strips move across each other as the wings change themselves, providing a smooth outer surface, the researchers explained.

Wind tunnel tests of these wings showed that they at least matched the aerodynamic (气动) properties of conventional wings, at about one­tenth the weight. “Initial tests using remotely piloted aircraft made with these wings have shown great promise，” said Benjamin Jenett, a graduate student at the Centre for Bits and Atoms at MIT.

The new modular structures the scientists developed could be manufactured quickly in mass quantities and then installed by teams of small robots. These modular structures also can be disassembled more easily, making repairs simpler.

“Still, the first aircraft built using this strategy will not be a passenger jet，” Gershenfeld said. “Instead, the technology will likely first be tested on unmanned aircrafts, leading to aircrafts flying for a long time, to help deliver Internet access or medicine to remote villages.”

1.Why is the Wright brothers' airplane mentioned in the text?

A. To show the history of aircrafts.

B. To show the development of wings.

C. To show the need to improve planes.

D. To show the structure of conventional planes.

2.What makes planes fly like birds when they tilt?

A. Their ailerons.    B. Wires and pulleys.

C. Changeable wings.    D. Mechanical control structures.

3.What is Paragraph 4 mainly about?

A. The shape of the new wings.

B. The purpose of the overlapping strips.

C. The working principle of the new wings.

D. The result of wind­tunnel tests of these wings.

4.What does the underlined word “disassemble” mean in Paragraph 6?

A. Replace.    B. Analyze.

C. Put away.    D. Take apart.

Answer

1.B

2.C

3.C

4.D

【解析】本文是一篇说明文，讲述了一种可以改变形状的机翼，能让飞机像鸟一样飞翔。

1.推理判断题。文章讲到了一种新型的机翼，还讲到了一种传统的机翼以及莱特兄弟的第一架飞机的机翼，这说明了机翼的发展变化过程。故选B。

2.细节理解题。第二段讲到，传统的飞机安装了副翼以适应飞机倾斜时的飞行。接着第三段讲到科学家一直在研究能改变形状让飞机像鸟一样飞行的机翼。可知，可改变形状的机翼能让飞机像鸟一样飞行。故选A。

3.细节理解题。第四段讲的是这种机翼的构成、飞行时机翼的变化以及变化的原因。这就是这种新型的机翼的工作原理。选C。

4.词义猜测题。前文讲到这种新的组合式的结构很容易生产和安装。据此可知，文章接下来讲到，这种结构也很容易拆解。故disassemble意为“拆解”。故选D。