英语句子分析the quality of life,especially as seen by the individu

英语句子分析
the quality of life,especially as seen by the individual,is meaningful in terms of the degree to which these various areas of life are available or provide satisfaction to the individual.
这句话怎么翻译?as seen 在句中作什么成分?degree后为什么加to?which指代什么?or连接哪两个句子?