In recent years there has been a remarkable increase in research into happiness. The researchers have (1) ________ a number of factors which contribute to a definition of happiness.

Fist of all, there is, in some people, a moderate genetic predisposition to be happy; in other words, happiness (2) _______ in families. And happiness seems to correlate quite strongly with the main dimensions of personality: extroverts are generally happier, neurotics are so.

Second, people often (3) _________ good social relations as a reason for their happiness. In particular, friends are a great (4) _________ of joy, partly because of the agreeable things they do together, partly because of the way friends use positive non-verbal signals such as caressing and touching, to affirm their friendship. Marriage and similar (5) ________ relationship can also form the basis of lasting happiness.

Third, job satisfaction undoubtedly (6) _________ overall satisfaction, and vice versa-perhaps this is why some people are happy in boring job: it works in both ways. Job satisfaction is caused not only by the essential nature of the work, but also by social interaction with co-workers. Unemployment, on the contrary, can be a serious cause of unhappiness.

Fourth, leisure is important because it is more under individual (7) _________ than most other causes of happiness. Activities (8) ___________ sport and music, and participation in voluntary work and social clubs of various kinds, can give great joy. This is partly because of the (9) __________ themselves, but also because of the social support of other group members – it is very strong (10) ________ the case of religious groups.