@prefix  : <http://example/> .
@prefix rdfs:    <http://www.w3.org/2000/01/rdf-schema#> .

:s1 :p :key1 .

:s2 :p :key2 .
:s3 :p :key3 .
:s4 :p :key4 .
:s5 :p :key5 .




:key1 rdfs:label "Key 1" .
:key2 rdfs:label "Key 2" .