<sentence> <Forall> <declare><Var>grade</Var></declare> <formula> <Implies> <if> <External> <content> <Atom> <op><Const type="rif:iri">op:numeric-greater-than</Const></op> <arg><Var>grade</Var></arg> <arg><Const type="xsd:decimal">4</Const></arg> </Atom> </content> </External> </if> <then> <Atom> <op><Const type="rif:iri">op:remove-grade</Const></op> <arg><Var>grade</Var></arg> </Atom> </then> </Implies> </formula> </Forall> </sentence>