OneeveningIwentoutandleftmy17-year-oldsoninchargeofhis8-year-oldbrotherand4-year-oldsister.Onthisoccasion,theworkwasmadelesstroublesomebythepresenceofhisgirlfriend.Ileftwithcompleteconfidencethattheolderchildrenwoulddoawonderfuljobofbabysittingtheyoungerchildren.Later,IdiscoveredthatcompleteconfidencewasthelastthingIshouldhavelefthomewith.

Ihaddecidedtoreturnhomeearlierthanplannedsothatmysonandhisgirlfriendcouldgoout.Icalledhomewiththishappynews.Butinsteadofhearinghischeerful,gratefulvoiceontheotherendoftheline,allIheardwasthesoundofatelephoneringing.

Itwas,Ishouldpointout,after10p.m.,whenthetwoyoungerchildrenshouldhavebeeninbed.andwhenthetwoolderchildrenshouldhavebeenansweringthephone.“I’llgivehimalesson.”Isaid.Idecidedtheymustbeoutside.Whytheymightbeoutsideat10∶30onawinternightIhadnoidea,butitwastheonlyexplanationIcouldcomeupwith.

Finally,indesperation,Icalledhisgirlfriend’shouse.Afterwhatseemedlikecountlessrings,hisgirlfriendanswered.“Yes,”shesaidbrightly,“He’srighthere.”

Hecameonthephone.Iwasnotmyusualcalm,rational(理智的)self.Afterall,oneoftherulesofsurvivalformodernparentsisthatyoucan’ttrustmodemteenagers.“Wherearethechildren?”Isaid.Hesaidtheywerewithhim.Theyhaddonenothingwrong.Mysonhadtakentheyoungerchildrenovertohisgirlfriend’shousejustforicecreamandcake.Thiswastoogoodtobebelieved.Well,itturnsoutthatIshouldn’thavebelievedit.Itwasonlypartofthetruth.

ThefollowingSaturdayeveningwewereatmyparentshome,celebratingmybirthday.Myoldestsongavemethechildren’sgifts.Mountedandframedwereaseriesoflovelycolorphotographsofmychildren,dressedintheirbestclothes,andwearingtheirmostwonderfulexpressions.Theyarepicturestotreasurealifetime,alltakenbythefatherofmyson’sgirlfriend.

小题1:Theauthorwentoutandlefthereldestsoninchargeoftheyoungerchildren

because .