Remember that an infinitive is a verb in its original form. It states what action/state of being is taking place but does not state who/what is performing/doing the action.

When you conjugate an infinitive, you are then establishing who/what is performing the action.

To conjugate a REGULAR -er ending infinitive follow the steps below:

1. Drop the -er ending from the infinitive . (That leaves you with what is called the verb stem.)

2. Add the correct ending to agree with the subject to the verb stem.

IF the subject is...	Add .....to the verb stem
yo	-o
tú	-es
usted (Ud.)	-e
él	-e
ella	-e
nosotros, nosotras	-emos
ustedes (Uds.)	-en
ellos	-en
ellas	-en

EXAMPLE OF THE CONJUGATION OF A REGULAR -er ENDING VERB... (comer-to eat)

IF the subject is...	verb stem	add to verb stem	Conjugated form of the verb
yo	com	-o	como
tú	com	-es	comes
usted (Ud.)	com	-e	come
él	com	-e	come
ella	com	-e	come
nosotros, nosotras	com	-emos	comemos
ustedes (Uds.)	com	-en	comen
ellos	com	-en	comen
ellas	com	-en	comen