摘要
Intheclass,theteacheraskedastudent,'Doyouknowwhatwordsareusedmostintheworld?'Thestudentthoughtquitealongtime,andatlast,hesaid,'Idon'tknow.'Theteacherwasgladandsaid,'Verygood,you'reright.Thesethreewords(I,don't,know)areusedmostintheworld.'HaveTheyDifferentMothers?Withthehelpofherfriend,ayoungmothertookherveryyoungtwinswhowereexactlyaliketothedoctor.Sincethewaitingareawasfull,thetwo
出版日期
2002年04月26日（中国期刊网平台首次上网日期，不代表论文的发表时间）
