Pene-, almost: peninsula, penult.
Per-, through, often intensive, throughout, thoroughly—and so wrongly: perspire, pervade; persist, perturb, pervert; pellucid, pilgrim (see ager). Fr. par-: pardon.
Post-, after: postdate, posthumous, post-mortem, postscript.
Pre-, before: precede, precursor, preëmpt, premature, premise, prevent.
Preter-, beyond, more than: preterite (of past time), preternatural.
Pro-, before, for, forward: proceed, proconsul, prologue, pronoun, provide; por-tend. Fr., pur: purchase, pursue.
Re-, red-, back, again: rebel, recede, recover, redeem.
Retro-, backwards: retroactive, retrograde, retrospect.
Se-, sed-, apart: seclude, secrete, sed-i-tion (a going apart), segregate.