był

third-person singular masculine past of być

on

he (for animate nouns), it (for inanimate nouns)

jak

• Pron

  how

• Conj
• Noun

natchnienie

inspiration (stimulating influence upon the intellect or emotions)

któremu

1. masculine dative singular of który
2. neuter dative singular of który

można

• Verb

  1. it is possible; one can (used to express possibility)
  2. it is possible; one is allowed

• Noun
• Adj

było

it was (third-person singular neuter past of być)

oprzeć

1. to lean onto, to put onto
2. to rest against, to place against
3. to base
4. to lean (assume or maintain a leaning posture)
5. to resist, to hold out, to withstand
6. to rely on, to be based on