erase: implies a rubbing or wiping out, as of letters or impressions, often in preparation for correction or replacement by new matter: ~ what you write and start over.


expunge: stress a removal or destruction that leaves no trace: ~ all references to the deposed leader.


cancel: implies an action, as marking, revoking or neutralizing, that nullifies or invalidates a thing: a crime that ~ all her good deeds.


efface: removal of an impression, impress, or image by damage, or elimination of a surface, or every sign of its existence: coins with date ~ by wear.


obliterate: implies a covering up or smearing, OR utter destruction that removes all traces of a thing's existence : a outdoor mural almost ~ by graffiti.


blot out: like obliterate, implies rendering a thing undecipherable or non-existent by smearing over or hiding completely: ~ offensive language with black ink.


delete: a deliberate exclusion, or a directive to the exclusion, of written matter: his editor ~ all unflattering references to others.


erase: 擦除以便改正或替换, expunge: 强调完全消除毁灭, 不留痕迹,  cancel: 使作废或无效, efface: 消除图像印象印记(3个im), obliterate: 覆盖弄污-->看不见，blot out: 根据解释，和obliterate完全相同,  delete: 删除书写内容。


记忆方法：1） EECEOBD联想成： CEO BED Edit， CEO躺床上编辑==>删除修改

          2) 删除的意思是移除某物mean to strike out or remove something so that it no longer has any effect or existence.