[laughingwithfee]

My teacher taught me some mnemonic devices to help me remember the stems for some verbs in the preterite: querer, poner, saber, poder.

poder - “He could eat pud-ding.”
saber - “He found out was-sup.” (saber also means to find out in the preterite tense)
poner - “He put the pus on the bus.” (slightly disgusting, but it works)
querer - “First you ‘quer’ and then you ‘kiss’.” (pronounce 'kiss' like 'quis' [kees] and pronounce 'quer' like 'care')

If anyone has any more mnemonics for preterite verbs, just let me know!