capable::申込取消[順番=N]/[申込者=A,被申込者=B] <= fact:回答[順番=M]/[行為者=A,受取人=B,種類=削除[対象=回答[順番=N]]]; def:申込[順番=N]/[申込者=A, 被申込者=B]; def:到達[順番=N]/[到達日時=S0]; def:到達[順番=M]/[到達日時=S1]; def:承諾[順番=K]; fact:回答[順番=K]/[発送日時=S2] ||{S0 =< S1, S0 =/= S1, S0 =< S2, S1 =< S2, S1 =/= S2}