When you want to conjugate a verb in Spanish or in English, the first thing that you need to do is recognize the basic verb form, which is called an infinitive. In English, infinitives have two parts: the infinitive marker to and the root of the verb, for example to talk, to eat, or to write.

There are infinitives in Spanish, and they have infinitive markers, too, but the markers and the root are rolled into a single word. The three infinitive markers in Spanish are ar, er, and ir, so Spanish infinitives will look something like this: comer, hablar, or escribir.

Infinitive is a pretty good name for this kind of verb. Infinitives don't have a specific person doing them or a specific time frame they take place in. So infinitives have an infinite number of possibilities. For you to take advantage of those possibilities, you have to conjugate your infinitive.

Conjugating means altering the infinitive so that your reader or speaker knows who is doing the verb and when. In English, it's a very easy process, but in Spanish, it's a little more complicated. Here's the reason: when you take the infinitive marker off an English verb, you have a real word that you can use. If you remove to from "to write", you're left with the perfect word for this sentence:

I write with a pen.

But when you remove an infinitive marker in Spanish, you're left with a piece of a word instead of a whole word. You can't use it until you alter it a little, and that alteration is called conjugating. Click here to learn how to conjugate the most common of Spanish verbs, verbs that end in -ar.