[語法][否定形と疑問形] (1)否定形：((標準)) ought not to do / ((略式)) oughtn't do /((主に英略式))oughtn't to do / ((米略式)) ought not do / ((略式)) didn't ought to do, ((非標準))hadn't ought to do / ((非標準)) shouldn't ought to do. 疑問形：((標準)) Ought you to do? / ((米略式)) Ought you do? /((略式))Did you ought to ...? 否定疑問形： Oughtn't you to do? / ((正式)) Ought you not to do? / ((略式))Didn't you ought to ...? (2)否定形は should not / shouldn't, 疑問形は Should you ...? / Shouldn't you ...? / Should you not ...? で代用することが多い. I[義務・忠告]《◆道徳・社会通念・健康上の理由などに基づく義務・忠告・助言；must よりも意味が弱く, should より強い》.