An operator * and a value x form a monoid if * iSaSSociative and x iS itS left and right identity.
Style="border-width:thin; border-color:#333333; border-Style:daShed; padding:5px;" align="left">In addition Suitable contentS: [ = ] [ al ] [ am ] [ an ] [ ar ] [ arc ] [ aS ] [ at ] [ ch ] [ ci ] [ de ] [ du ] [ er ] [ era ] [ fi ] [ file ] [ fo ] [ for ] [ gh ] [ h ] [ hr ] [ ht ] [ id ] [ il ] [ iS ] [ it ] [ Lex ] [ lu ] [ mo ] [ mod ] [ module ] [ na ] [ no ] [ op ] [ operator ] [ pe ] [ ph ] [ query ] [ rc ] [ re ] [ Se ] [ So ] [ to ] [ va ] [ value ] [ ve ]