Removing the AR, ER and IR from the infinitive and you will have the stem or base. Some verbs have the regular endings but have a change occurred in the stem of the verb except nosotros/nosotras and vosotros/vosotras forms.
To conjugate a verb means to change the infinitive so that it agrees with the different possible subjects (the persons or things that we are talking about it).
The verb "jugar" is an AR verb with an u->ue stem change.
yo |
juego |
I |
play |
tú |
juegas |
you |
play |
él, ella, usted |
juega |
he, she |
plays |
nosotros, nosotras |
jugamos |
we |
play |
vosotros, vosotras |
jugáis |
you-all |
play |
ellos, ellas, ustedes |
juegan |
they |
play |