A、They get married before they buy their own house. B、More people get divorced and do not remarry soon. C、They attend local coll

"There is a senseless idea that children grow up and leave home when they’re 18, and the truth is far from that, "says sociologist Larry Bumpass of the University of Wisconsin. Today, unexpected numbers of young adults are living with their parents. "There is a major shift in the middle class," declares sociologist Allan Schnaiberg of Northwestern University, whose son, 19, moved back in after an absence of eight months.
    Analysts cite a variety of reasons for this return to the nest. The marriage age is rising, a condition that makes home and its pleasantness particularly attractive to young people. A high divorce rate and a declining remarriage rate are sending economically pressed and emotionally hurt survivors back to parental Shelter. For some, the expense of an away-from-home college education has become so excessively great that many students now attend local schools. Even after graduation, young people find their wings clipped by high housing costs.
    Just how long should adult children live with their parents before moving on? Most psychologists feel lengthy homecomings are a mistake. Children, struggling to establish separate identities, can end up with "a sense of inadequacy, defeat and failure". And aging parents, who should be enjoying some financial and personal freedom, find themselves stuck with responsibilities.  Many agree that brief visits, however, can work beneficially.