4、Bird strikes are extremely rare in the airline industry, which has one of the best safety records of any mode of transport. However, birds are a known threat （威脅）at airports, particularly where runways are close to water, such as the airport in New York.

Airports take a range of measures against bird strikes, which usually occur around take – off or landing, when a plane flies into a flock （鳥群）and sucks birds into its engines. They sometimes keep the grass long near runways, because flocks avoid areas that could contain dangerous animals. Staff also use “noise guns” to disperse flocks that settle on the site. Airports sometimes hire eagles, too.

A professional pilots’ group said last night that the apparent disabling of two engines by the birds strike in New York was a “terrible coincidence” and praised the bravery and skill of the pilot who landed in the Hudson River.

“It is quite clear that the pilot got everything absolutely right. Witness reports suggest that the plane hit a flock of birds, and I must have damaged both engines because if it had been one, he would have been able to continue.”

“Engines are designed extremely well now and in general they are better able to cope with bird strikes,” said Martin Chalk, president of the European Pilot Association. “It is an extremely rare occurrence. It would appear that worse has been avoided due to the skills and training of the crew.”

A severe bird strike disabled a plane at Rome’s airport in November last year, when a Frankfurt to Rome jet carrying 166 passengers had to make an emergency landing. The airport is known to have problems with flocks of geese.

In the UK, a plane had to make an emergency landing at Manchester airport in April 2007 after two herons where sucked into the engine of a passenger plane shortly after taking off for Rome.

The low but unavoidable threat of bird strikes is one of the reasons why many people are opposing the proposed construction of a new international airport in swampland near London. According to a 2003 report, “the risks posed by bird strikes would be expected to be greater at sites near major areas of water.”

1．What was the cause of the air accidents described in the passage?

       A．Damage to the plane’s engine.

       B．Loss of vision by the pilot due to birds.

       C．The runway being too close to the river.

       D．Failure of the airport to manage the bird problem.

2．The underlined word “They” （paragraph 2） refers to “        ”.

       A．Planes                 B．Airports               C．Birds                   D．Pilots

3．Why are plane accidents caused by birds increasingly rare?

       A．There are fewer birds living around airports.

       B．Pilots and crew are trained to ignore bird strikes.

       C．Pilots know how to avoid brides when taking off.

       D．Plane engines are better designed than in the past.

4．How many serious bird strike accidents are mentioned in passage?

       A．2                        B．3                        C．4                        D．5

5．Which of the following can be inferred from the passage?

       A．It is safer to build airports away from wetlands.

       B．Birds will continue to be a serious danger to plane travelers.

       C．Most accidents occur when planes are landing.

       D．The passengers were lucky to survive the crash.