for $item in collection("sortie-treetagger-3208.txt.xml")//item for $element in $item //element let $sonfere := $element/following-sibling::element[1] let $sonfere2 := $element/following-sibling::element[2] let $sonfere3 := $element/following-sibling::element[3] where $element/data[1][contains(text(),"DET")] and $sonfere/data[1] = "NOM" and $sonfere2/data[1] = "PRP" and $sonfere3/data[1] = "NOM" return concat($element/data[3],' ',$sonfere/data[3],' ',$sonfere2/data[3],' ',$sonfere3/data[3])