题目内容：

    In a national survey, just 1 in 3 students thought that smoking on some days, but not others, can cause a lot of harm. This smoking pattern is common. It is also dangerous. In fact, its health risks are about the same as smoking heavily, report Stephen Amrock and Michael Weitzman. Their new study’s findings show that most kids do not see risks in smoking the occasional (偶尔的) cigarette.

For their study, Amrock and Weitzman analyzed data from the 2012 National Youth Tobacco Survey. It had probed (探究) tobacco-related knowledge, attitudes and behaviors in 24,658 students. All were in grades 6 through 12 and lived throughout the 50 U. S. states and the district of Columbia.

Most teens knew that heavy smoking can be harmful. About 2 in every 3 students recognized that smoking even just a few cigarettes each day can be harmful (有危害的). Only 1 in3 students, however, recognized that occasional—non-daily—smoking is harmful. Among teens who smoke this way—intermittently—just 1 out of every 7 understood their habit was dangerous.

Occasional smoking is not safe, so “we really need to have a conversation” with whoever thinks otherwise, notes Dave Dobbins. He heads research and public education at Legacy, a group based in Washington, D. C. It encourages teens to reject tobacco. “Intermittent smoking carries lots of risks,” Dobbins explains. These include the chance that light use will progress to heavier smoking. “We explain to kids that light smoking is smoking,” says Dobbins, who was not connected with the study. And, he adds, his group points out that “the dangers begin right away”.

Adults who are light or intermittent smokers are those most willing and able to quit. Amrock and Weitzman note. Most smokers start by age 18. That’s why the NYU School of Medicine researchers suggest anti-smoking efforts should target youth who today are light or occasional smokers.

1.What’s the text mainly about?

A.Occasional smoking. B.Health and smoking.

C.The number of smokers. D.Anti-smoking efforts.

2.Where can you find the data showing students’ views on different smoking patterns?

A.In Paragraph 1. B.In Paragraph 3.

C.In Paragraph 2. D.In Paragraph 4.

3.What’s the meaning of the underlined “intermittently” in Paragraph 3?

A.Heavily. B.Continuously.

C.Occasionally. D.Purposefully.

4.Dave Dobbins agrees that ________.

A.dangers of kids’ light smoking appear in no time

B.light smoking is sure to result in heavy smoking

C.most teens have realized the risks of light smoking

D.light smokers are likely to quit smoking naturally