??ͷ?????ڽӵ?һ???µ?JD??????Ҫ???IJ???????ȥ?Һ?ѡ?ˣ?Ӧ?þ???????˼??һЩ?????ε????⡣ͬʱ????ǰ??Ӧ????JD?????ʼǣ?????Ŀ?????????в??Ͻ??е????????IJ???֮??????ȡ???????JD?????????????ܹ????ӿ??ٵ??ҵ????ʵ???ѡ??????JD??ͨ????????1??ְλȫ????ʲô??2???????ص㣿3????ְλmust???ϵ???????ʲô??Prefer???ϵ???????ʲô??4????Ҫ??ѡ?˽???ĺ?????????ʲô??5????Ƹԭ????ʲô???????̶?????ϣ????ʱ???ڣ?Ϊʲô??6??ǰ?λ????Σ???????ְ???????ҵ????˹?ͨ???ķ??ű?????????ʲô????ְԭ????ʲ