微笑吧，幸福的人们更长寿

短语讲解：

1. Almost 4,000 people, enrolled in a long-term aging study in Britain, were asked to score how they were feeling on a particular day.

enroll in (使)加入
例句：I should like to enroll all my children in the swimming class.
我愿意让我的孩子们都参加游泳班。

2. In contrast to previous studies, in this research the people were asked how they felt at that moment.

in contrast to相比之下; 与……相反
例句：In contrast to her sister, she is very tall.
与姐姐相比, 她个子很高。

3. But Steptoe says psychologists have shown that people are not good at answering that type of question.

be good at擅长
例句：He is good at languages.
他善于学语言。

4. For example, if their favorite football team lost the previous weekend or something like that, they would rate themselves less happy over the whole week, even though it might not actually have affected them in that way.

for example例如, 譬如
例句：There are many sources of air pollution; exhaust fumes, for example.
空气污染有许多来源, 例如废气。
even though即使、虽然
例句：He's the best teacher even though he has the least experience.
尽管他经验最少, 但教得最好。