21. To protect yourself from swine flu, it is a good idea to __________.

　　A) have baths frequently B) cover your coughs and sneezes

　　C) stay home from work or school if you feel tired D) eat an apple every day

　　22. The underlined phrase “warding off” in the second paragraph can be replaced by “_______”.

　　A) investigating B) increasing C) preventing D) decreasing

　　23. What does Richard Besser mean by saying “Control of ... getting infected.”?

　　A) It is the government’s responsibility to fight against infectious diseases.

　　B) It is the patients’ responsibility to prevent the spread of infectious diseases.

　　C) It is everybody’s responsibility to control the outbreak of infectious diseases.

　　D) It is doctors’ and experts’ responsibility to fight against infectious diseases.

　　24. According to the passage, what do we know about swine flu?

　　A) Swine flu can be transmitted easily among pigs but not among people.

　　B) Symptoms of swine flu are different from those of regular seasonal influenza.

　　C) People with swine flu often get a stomachache, headache and toothache.

　　D) Swine flu is a virus that has acquired the ability to pass from person to person.

　　25. What does Richard Besser think of wearing a face mask?

　　A) It can protect people from getting infected.

　　B) It can make people feel comfortable and is affordable.

　　C) It isn’t as effective as hand-washing and covering your mouth when you cough or sneeze.

　　D) It is more effective than hand-washing and covering coughs and sneezes.