Numerous 4 letter words begin with the letter p. A few of those words include pace, pack, pact, pads, page, paid, pail, pain, pair, pale, palm, pane, pang, pans, pant, papa, pare, park, pars, part, pass, past, pate, path, pave, pawn, pays, peak, peal, pear, peas, peat, peck, peek, peel, peep, peer, pegs, pelt, pens, perk, perm, peso, pest, pets, pews, pier, pies, pigs, pike, pine, ping, pink, pins, pint, pipe, pits, pity, plan, play, plea, plod, plop, plow, ploy, plug, plum, plus, pods, poem, poet, poke, poky, pole, poll, polo, pomp, pond, pony, pool, poor, pope, pork, port, post, pots, pour, pout, pray, prep, prom, pros, pubs, puff, pull, pump, punk, punt, pure, push and putt.
Princess!
some words include:pabulumspachadompachalicpachinkopachisispachoulipachucospacifiedpacifierpacifiespacifismpacifistpackablea full list of words beginning with P containing 8 letters can be found here (see related links), although this list doesn't include every 8 letter word containing the letter P.
8 letter words w/final letter P:raindropairstripback-flipbackdropsubgroupsidesteptownshipdoorstopbackstopworkshoplordshiphockshopteardropbookshoplollipoplockstepsidestepscrew-topoversteplong-jumpnightcappawnshopfiretrapfollowupbullwhipchange-upblacktopbakeshop
plans
people
The silent letter in "mnemonic" is the "m" at the beginning of the word. In "pneumonia," the silent letter is the "p" at the beginning of the word.
Particle.
Another word for holy is pious.
prow
peripheral
presume
poignant