Apo-, from, away from, off: apology, apostle, apostrophe, aphelion, apogee (gē = earth), apostasy.
Arch-, chief: archangel, archbishop, archfiend, archi-tect.
Auto-, self: autocrat, autograph, automobile, autonomy, automatic, aut-opsy.
Cata-, down, (thoroughly): cataract, catastrophe, catechise, catalogue, (a complete numbering).
Dia-, through, (between): diagonal, diagram, dialogue, diapason, diaphragm.
Dis-, di-, twice, doubly: dissyllable, di-phthong, dilemma.
Dys-, ill, bad: dysentery, dyspepsia.
Ec-, ex-, out, out of: ec-centric, ec-lipse, ec-stasy, exegesis, exodus, exorcise.
En-, in: energy, emblem, emphasis, empiric, encomium, encyclic, endo-gen.