ean (Greek #1437)
a conditional particle; in case that, provided, etc.; often used in connection with other particles to denote indefiniteness or uncertainty
KJV usage: before, but, except, (and) if, (if) so, (what-, whither-)soever, though, when (-soever), whether (or), to whom, (who-)so(-ever). See 3361.
Pronounce: eh-an'
Origin: from 1487 and 302
oun (Greek #3767)
(adverbially) certainly, or (conjunctionally) accordingly
KJV usage: and (so, truly), but, now (then), so (likewise then), then, therefore, verily, wherefore.
Pronounce: oon
Origin: apparently a primary word