There do not seem to be any sutiable synonyms except "planting" (for burying).
Perhaps the synonym sought was for internment, which could include prison.
people
plans
Particle.
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.
"Pristine" is a word that can be synonymous with holy and starts with the letter P.
prow
peripheral
presume
poignant
props
prattle
puce