你说的基本正确。http://zhidao.baidu.com/question/252673529.html&__bd_tkn__=69a3406438268603540ee772b7bf3dfd8a1cd8f68078338d51fed8133ea5c69d362ad36bb4bcda3b39bb3949f6bbe47087ac3af56e60b1f4e7eb60157a59ff349a64acfa570f03de0125270fd732cd094973e8717d2fc884da454508742a372ecc600d414bc0dfac9a7d8eaccbdc8d02c8342af247a9