The shift away from family life to solo lifestyle, observes a French sociologist, is part of the ”irresistible momentum of individualism” over the last century.此句当中observe是做什么成分呢?怎么翻译这个句子呢?谢谢老师
Most tests require collecting cells by webbing saliva in the mouth and sending it to the company for testing.All tests require a potential candidate with whom to compare DNA.这句话该怎么理解呢?