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Irregular YO Verbs

 
As the title implies, these particular verbs have irregular forms in the 1st person singular (or ¨yo¨ form) that have to be memorized, as there is no definite pattern for recognizing them.  However, their conjugations in the other forms do follow regular conjugation rules.  

There are 3 categories of Irregular YO verbs.  
  1. Verbs that end in -go
  2. Verbs that end in -oy
  3. Verbs that end in -zco
  4. Verbs that are miscellaneous. 
1)  Your common verbs that end in -go are:
hacer    →    hago           
poner   →    pongo           
*decir   →   digo
*tener  →   tengo         
*venir  →   vengo

(*These particular verbs are also stem-changers in the boot)
This also applies to any variations of these verbs, they too will have an irregular "yo" conjugation. 
​(rehacer, proponer, retener, mantener, prevenir, predecir, etc.)
Here are the conjugations for HACER, and you can see that the YO form is irregular, but the other conjugations follow regular rules. 
2)  Your common verbs that end in -oy are:
​estar  →    estoy          
ser     →     soy        
ir        →     voy      
dar     →     doy
Do keep in mind, that IR and SER have are unique in that they do not follow regular conjugation rules.  They have their own unique verb conjugations and they just have to be memorized. 
3)  Your common verbs that end in -zco are:
conducir    →   conduzco         
conocer     →   conozco

This will also apply to any other verbs that you come across that end with -cir or -cer. 
(producir, reconocer, complacer, etc.)
4)  Then there are those few verbs that do not follow any specific pattern. 
​saber    →    sé
ver        →    veo
These are flashcards for the vocabulary of irregular YO Verbs.
This Quizlet set that will help you memorize the irregular YO forms. 
This Quizlet set is to help you memorize the irregular YO forms.