Conjugating -ER and -IR verbs
After -ar come the other two verb families: -er, with comer, beber, leer and vender, and -ir, with vivir, escribir and abrir. Their endings sit so close together that they are very nearly one group — across the entire present tense the two families differ in exactly one form, the nosotros one: comemos but vivimos. Learn -er properly and you get -ir almost for free.
The -ER group
Take comer, to eat. Trim off the -er and the stem com- is what remains; five endings go onto that stem and they are the whole present tense. yo como, tú comes, él come / ella come / usted come, nosotros comemos, ustedes comen / ellos comen / ellas comen. The chant is short: como, comes, come, comemos, comen. Say it out loud four or five times — your mouth will learn it before your head does.
The -IR group
vivir, to live, runs on the same machine. Stem viv-, and then: yo vivo, tú vives, él vive / ella vive / usted vive, nosotros vivimos, ustedes viven / ellos viven / ellas viven. Chant it the same way: vivo, vives, vive, vivimos, viven. Notice how little new there was to learn.
One ending apart
Now lay the two chants side by side. como and vivo. comes and vives. come and vive. comen and viven. Identical, four times in a row. The one place the families part company is nosotros, where -er gives -emos and -ir gives -imos: comemos but vivimos, leemos but escribimos, bebemos but abrimos. That single vowel is the entire difference between the two groups. Get nosotros right and the rest looks after itself.
Four more verbs, same machine
leer, to read, gives leo, lees, lee, leemos, leen — both vowels are pronounced, so leemos has two clear e sounds. beber, to drink, gives bebo, bebes, bebe, bebemos, beben. escribir, to write, gives escribo, escribes, escribe, escribimos, escriben. abrir, to open, gives abro, abres, abre, abrimos, abren. One habit worth picking up early: at a table you will hear tomar far more often than beber — ¿Qué toman?, tomamos café, tomo agua — but beber is understood everywhere and shows the -er shape cleanly, so it is the one to learn the pattern on.
All three groups at once
yo: hablo, como, vivo. tú: hablas, comes, vives. usted: habla, come, vive. nosotros: hablamos, comemos, vivimos. ustedes: hablan, comen, viven. Read down the rows and only nosotros shows three genuinely different shapes. Look closely at the last row too: ustedes is the plural 'you' for everybody — your brothers, your closest friends, a room full of strangers — and it always takes the same form as ellos. Telling your family ustedes comen mucho is not stiff and not formal; it is simply how the plural 'you' is said from Tijuana to Ushuaia.
