what are the names of cng engines?
Entity Entity
m.0jt2zqq m.0hgcqtx
GM Small Gasoline Engine Honda 1.8L 4 Cylinder 110 hp 106 ft-lbs CNG
class entity
automotive.engine m.03jj2w
automotive.engine automotive.fuel
Engine cng
none none
automotive.engine.fuels_used
Fuels Used
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (?x0 AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :automotive.engine . 
VALUES ?x1 { :m.03jj2w } 
?x0 :automotive.engine.fuels_used ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(AND automotive.engine (JOIN automotive.engine.fuels_used m.03jj2w))