题目内容：

The 2009 outbreak of influenza H1N1 virus（甲型流感病毒）is also called“swine flu（猪流感）”. It is a new flu virus that was first found in April, 2009. This kind of virus can make people ill and is spreading from person-to-person, causing a growing outbreak of illness first in the United States and Mexico. Later, an increasing number of sick people are being reported in many other countries.

    Why and how the swine flu started in humans is still unknown. The first sick people were found in the U. S. ,but soon it was found out that the new virus had much to do with an earlier outbreak of late-season flu in Mexico. Several days later hundreds of sick people were discovered in Mexico, with more sick people found in the U. S. , Australia, Europe and many other countries as well. The World Health Organization（WHO）worried that it could become a worldwide flu.

    Although scientists have noticed that the outbreak has not been as serious as those in history, other health officials（官员）worry about what might happen later in the year, saying that “we are not seeing any sign（迹象）of this coming to an end. The flu might be spreading at a crazy speed. The number of sick people is expected to rise as the new flu spreads across the countries.” Besides, the new virus could change its form over the coming months. Leading to a new and more dangerous flu outbreak later in the year.

1.The virus of swine flu is spreading mainly through           .

A. pigs    B. birds    C. any animal    D. humans

2.The new virus was first produced most probably in           .

A. Mexico    B. America    C. Australia    D. Europe

3.What the health officials say is to          .

A. ask people not to pay much attention to the new flu

B. tell people the new flu will soon come to an end

C. make people realize the danger of the new flu

D. announce the spreading speed of the new flu

4.Which of the following statements is true ?

A. The influenza H1N1 virus has spread for several years.

B. The swine flu has been spreading across a lot of countries.

C. The outbreak of the new flu has been the most serious so far.

D. The new virus will come to its end in a short time.

5.Which can be the best title（题目）of this passage ?

A. The Most Dangerous New Illness    B. 2009 Swine Flu Outbreak

C. What Is Influenza H1N1 Virus ?    D. How Is the New Flu Spreading ?