O字开头的单词或词组
operation manualopen onobituaryosteoarthritisovercameoscoral examinationOSFonce or twiceoriginatingOsirisoscillationorthonormalO2ornateoff-peakoutstretchordainoverdrawoff the cuffover weightopt foroil pressoverfishone-eyedon the runorder formon the alertoffenceoverindulgenceochobjectivityoverrateoperandorganizationalOne cannot make a silk purse out of a sow's earovertookonrushopiumobservableomeletteoxycodone
