【题目】 Pigeons (鸽子) may be considered mice of the sky, but some scientists have found greater value in these urban birds: the blueprint for a new generation of flying machines.

Birds can transform the shape of their wings by fanning out their feathers or moving them closer together. Those adjustments allow birds to cut through the sky more flexibly than rigid drones (无人机). Now, using new insights into exactly how pigeons ‘joints control the spread of their wing feathers, researchers have built a robotic pigeon. This research paves the way for creating more light aircraft, says Dario Floreano, a roboticist in Switzerland not involved in the work.

“What’s really cool about this robot is that you can make adjustments in a robotic wing that you could never do when studying flight in a bird”, says David Lentink, an engineer and biologist at Stanford University. A controllable robotic pigeon solves that problem. In flight tests, Lentink’s team observed that bending only the fingers of one wing eased the robot into a banked turn-offering the first evidence that birds may sometimes use just their fingers to direct in flight. In a second study, Lentink’s group used their robotic wing design to confirm another insight into bird flight: how gaps are prevented from forming between feathers on extended wings.

This is the best set of robotic wings yet for testing how birds adjust their flight feathers to move through the air, says Tyson Hedrick, a biomechanist. But “there’s plenty of room for improvement.” For instance, a future flying robot could include a shoulder joint to investigate how waving a bird’s wings up and down influences flight, he says.

1What is the newly-found worth of pigeons?

A.They help study other species.

B.They protect other urban birds.

C.They provide proof of mice’s harm.

D.They inspire a new aircraft.

2What is Dario Floreano’s attitude to the research?

A.Negative.B.Positive.

C.Neutral.D.Critical.

3What do the underlined words “that problem” in paragraph 3 refer to?

A.Pigeons in flight can hardly be observed.

B.People can’t make adjustments in birds’ wings.

C.It is difficult for pigeons to make a banked turn.

D.Pigeons fail to control the spread of their wing feathers.

4Where does the text probably come from?

A.A travel journal.

B.A travel brochure.

C.A science fiction.

D.A science magazine.

【题目】Directions: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.

Minimum wage laws in the U.S. were first introduced during the 1930s in response to the Great Depression. This period was 1 by falling output, falling prices, and falling employment. The National Industrial Recovery Act (NIRA) of 1933 attempted to stop this downward trend by encouraging the 2 of trade association agreements that established the lowest price and minimum wages. This was the first time that minimum wages were introduced in major industries. But in 1935, the U.S. Supreme Court ruled that the NIRA was unlawful, and these initial minimum wage agreements came to an end.

In 1938, the Fair Labor Standards Act (FLSA) established a national minimum wage of $0.25 an hour. This Act 3 only applied to a relatively small share of the labor force, but has been 4 over time so that it now applies to about 90% of all nonsupervisory workers.

Introductory economies textbooks usually first introduce the minimum wage as an application of demand and supply analysis. This starting discussion is usually based on the following 5: the labor market is perfectly competitive, the minimum wage covers all workers, and worker productivity is 6 by the wage rate.

While minimum wage increases generally receive 7 public support, economists have generally argued that such laws will result in an increase in the unemployment rate in low-wage labor markets.

An issue related to that of a minimum wage is a growing movement for a “living wage”.Living wage proposals suggest that the 8 minimum wage is too low to allow families to be above the poverty level. Now, 9 of this view support “living wage laws” that require the local government to only accept contracts from firms that pay their workers a wage that is high enough to 10 the worker above the poverty line. Under Baltimore’s “living wage” requirement, firms must pay a worker an hourly wage that will allow a full-time worker to receive an annual income greater than or equal to the poverty level for a family of three.

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