Smokers in England have been asked to give up smoking for 28 days this month, in a campaign backed by Cancer Research UK and the British Heart Foundation.

Research shows people who manage not to light up for this length of time are five times more likely to kick the habit for good.

Public health experts say campaigns that include a combination of hard-hitting adverts and supportive messages work best.

Quitting smoking can be difficult. People are much more likely to succeed if they get support than if they try to do it alone and go cold turkey.

Robert West, Director of Tobacco Studies at University College London, points out how peer pressure can prevent a tobacco addict's resolve going up in smoke.

"We are social animals, we are herd animals and we are influenced by each other," he said.

The initiative has met some scepticism among readers of the BBC News Online website. Some compared it to asking people to stop eating as a way of combating obesity. Others doubt the campaign's effectiveness.

"Its weakness is that it fails to address why a person smokes, and these reasons are as varied as the number of smokers", says someone who signed as BluesBerry.

Another reader, Cazz, has decided to give it some credit. He says: "Campaigns like this won't necessarily prompt the majority of smokers to quit, but may prompt those thinking about quitting to set a date and try. Surely it's worth a shot."

The number of smokers in England is estimated at 8 million.

According to the Department of Health, smoking is the biggest cause of premature death in the country.

Glossary 词汇表：
to give up放弃
to back支持
to light up点燃
to kick the habit要戒掉恶习
a public health expert公共健康专家
hard-hitting强硬的
to quit戒掉，放弃
to go cold turkey突然停止(做某事)
peer pressure同伴压力
an addict瘾君子
to go up in smoke化为乌有，成为泡影
scepticism怀疑，怀疑主义
to address解决
to prompt促使
to be worth a shot值得一试的
premature过早