PBL是什么意思？ 百度知道: Revision history
Diff selection: mark the radio boxes of the versions to compare and hit enter or the button at the bottom.
Legend: (cur) = difference with current version,
(last) = difference with preceding version, M = minor edit.
Diff selection: mark the radio boxes of the versions to compare and hit enter or the button at the bottom.
Legend: (cur) = difference with current version,
(last) = difference with preceding version, M = minor edit.