9. Avian influenza is highly contagious and harmful; There are many kinds of avian influenza viruses, and the causes of avian influenza are very complicated. People are just speculating about the cause of the bird flu outbreak. (3 points. Get full marks for answering two points)

10, which specifically and accurately shows the great infectivity and harmfulness of avian influenza. (3 points)

1 1, no. Because people are just speculating about the cause of the bird flu outbreak. If it is removed, it will become affirmative, which is inconsistent with the facts and does not meet the requirements of the accuracy of the interpretation language. (3 points)

12, people can't completely determine the cause of the outbreak of avian influenza and the source of infection, so they can only speculate. (3 points)

13 for example, all countries in the world should coordinate their efforts to prevent bird flu from spreading to humans; Prevent contact infection; For individuals, we should pay attention to good health and maintain good immunity; Before eating poultry products, they should be cooked at high temperature to kill the virus; It is forbidden to eat dead birds; Cut off the transmission route of the virus and take scientific epidemic prevention measures. (4 points. Open question, as long as students can combine what they have learned, such as how to determine the source of infection and how to isolate it in biology, can have certain scientific truth.