Compound microscopes are optical microscopes which have a series of lenses: the ocular lens (in the eyepiece) and the objective lenses (close to the sample).
(Compound microscopes; are; optical microscopes which have a series of lenses) (optical microscopes; have; a series of lenses)
Compound microscopes optical microscopes
are have
optical microscopes which have a series of lenses
a series of lenses