The verbs have been grouped together by the irregularity of the conjugation.
If the last syllable is a vowel, the 'u' gets an accent
If the last syllable is a vowel, the 'i' gets an accent
If the conjugation adds an 'e' to the stem, then the 'c' is replaced by 'qu'
if the conjugation adds an 'a' or an 'o' to the stem, then the 'c' is changed to 'z'
if the conjugation adds an 'e' to the stem, then the 'z' is changed to 'c'
if the conjugation adds an 'a' or an 'o' to the stem, then the 'g' is changed to 'j'
If the conjugation adds an 'e' to the stem, then the 'g' is replaced by 'gu'
the 'u' disappears if the verb conjugation adds an 'a' or an 'o'
the 'e' goes to 'ie' if the 'e' is in an accented syllable
the 'o' changes to 'ue' if the 'o' occurs in a stressed syllable
'o' changes to 'ue' if the 'o' occurs in the accented syllable
o -> ue or sometimes o -> u
e -> i in some instances: no pattern listed
'e' could go to 'ie' or 'i'
the reír verbs
c -> zc if an 'a' or an 'o' is added to the stem by the conjugation
the 'c' changes to 'zc' if the conjugation gives the stem an 'a' or an 'o'
c -> zc if the conjugation adds an 'a' or an 'o' to the stem; some c -> j changes in the subjunctive
two changes: it will be better just to show the complete conjugations
trocar- was not listed in the dictionary
two changes, one involving changing u to ue and the other adding a u to the ending
the 'u' changes to 'ü' if the conjugation gives the stem an 'a', an 'e', or an 'o'
'ui' can change to 'uy' (no pattern established here)
predecir verbs- no code given
tener verbs- no code given
traer verbs- no code given
venir verbs- no code given
I'm not certain how to classify the irregular verbs listed below:
adecuar - to adapt
evacuar - to evacuate
diferenciar - to distinguish
paliar - to ease, relieve, justify
abreviar - to shorten, to cut short, to hurry up
acopiar - to gather, to buy up
acuciar - to goad
agenciar (algo a alguien) - to fix (somebody up with something)
agraciar - to make more attractive
cambiar - to change
desprestigiar - to discredit
asalariar - to take on
comerciar - to trade
agraviar - to offend
anunciar - to announce, to herald
columpiar - to swing
despreciar - to scorn, to spurn
apremiar - to urge
apropiar a - to adapt to
compendiar - to summarize
arreciar - to get worse
asociar - to associate
concienciarse - to become aware
contagiar - to infect, to transmit
desperdiciar - to wate, to squander
disociar (de) - to dissociate (from)
distanciar - to drive apart
escanciar - to serve, to pour out
estudiar - to study
evidenciar - to demonstrate
intercambiar - to exchange
limpiar - to clean, to wipe
menospreciar - to scorn, to despise, to undervalue