Long-term use can produce unwanted effects in some people.

VOA: special.2009.04.07

Research on subjective wellbeing-- the term that psychologists use to capture happiness essentially has been going on for very, very long time.

对幸福的研究-,心理学家用这个词来描述快乐,已经进行了很多年。

哈佛公开课 - 幸福课课程节选

The researchers used a national long-term survey of adolescent health to investigate the relationship between media use and depression.

VOA: special.2009.02.11

American researchers used a national long-term survey of adolescent health to investigate the link between media use and depression.

VOA: special.2009.03.10

Doctors use such databases to monitor the long-term well-being of patients undergoing many kinds of treatments.

VOA: standard.2010.01.01

"President Obama has made it a clear commitment to revolutionize the way that we use energy, including mandatory cap and trade legislation, long-term submissions reductions goals and a commitment to renewable energy technologies,"

VOA: standard.2009.08.31