Erudition, knowledge, profundity, sagacity, sense, wisdom.
Eternal, imperishable, interminable, perennial, perpetual, unfailing.
Excuse, pretense, pretext, subterfuge.
Exemption, immunity, liberty, license, privilege.
Explicit, express.
Faint, faint-hearted, faltering, half-hearted, irresolute, languid, listless, purposeless.
Faithful, loyal, stanch, trustworthy, trusty.
Fanciful, fantastic, grotesque, imaginative, visionary.
Fling, gibe, jeer, mock, scoff, sneer, taunt.
Flock, bevy, brood, covey, drove, herd, litter, pack.