Today, people travel around the world by air and enjoy the great convenience it brings, but studies show that air travel is bad for the environment. It’s responsible for about three percent of the world’s greenhouse gas emissions (排放物). Then do we have to give up flying to save the planet? Maybe not.

Last month, a British airline (航空公司) operated a flight (航班) called Flight 100. It flew from London to New York with some reporters, engineers and government officers on it. There were no paying passengers. The flight was special because the plane used waste fats and plant sugars as fuel (燃料). As a new kind of green fuel, it was different from the traditional fuel and it cut the flight’s pollution by 70 percent according to the company. Some people said that the flight meant a lot. Many more people wanted to have a try on the flight.

However, there are still problems. For one thing, the green fuel costs five times as much as the traditional fuel. For another, it is difficult to make enough green fuel for all the flights around the world in a short time. To provide enough fuel for a large number of planes, farmers will have to grow more plants. Therefore, more forests will be cut down for farmland.

For now, the British airline and other airlines have no plan to provide similar flights for the public. There is still a long way to go before air travel becomes greener. But one day in the future, such flights may become common and the greenhouse gas emissions may be reduced.

【小题1】According to the text, we know air travel is _______.

A．good for the forests	B．helpful to the planet
C．bad for the travelers	D．harmful to the environment

【小题2】Flight 100 was special because _______.

A．it was from London to New York	B．a new kind of green fuel was used
C．it was operated by a British airline	D．some government officers were on it

【小题3】What is Paragraph 3 mainly about?

A．Advantages of taking the flight.	B．Costs of making traditional fuel.
C．Problems of using the green fuel.	D．Difficulties of planting more trees.

【小题4】What can we infer (推断) from the text?

A．The public have already taken similar flights.

B．Air travel will become greener in a short time.

C．All airlines are against producing the green fuel.

D．More work needs to be done to make air travel cleaner.