Conjugating -are verbs in the present
Italian verbs come in three families based on the infinitive ending: -are, -ere, -ire. The -are group is the biggest β and the most regular. Drop the -are, add the personal ending. Once you've memorized the six endings (-o, -i, -a, -iamo, -ate, -ano), you can conjugate parlare, mangiare, abitare, lavorare, comprare and dozens more in the present tense.
The pattern: stem + ending
From parlare (to speak), drop -are to get the stem parl-. Now add the endings: io parlo, tu parli, lui/lei parla, noi parliamo, voi parlate, loro parlano. Memorize the rhythm β -o, -i, -a, -iamo, -ate, -ano β and you have every regular -are verb in the present tense. Italians normally drop the pronoun: Parlo italiano beats Io parlo italiano.
Stress where you'd expect it β except loro
Five of the six forms stress the syllable you'd expect: par-LO, PAR-li, PAR-la, par-LIA-mo, par-LA-te. The odd one out is loro: stress jumps back onto the stem β PAR-la-no, not par-LA-no. Same with mangiano: MAN-gia-no. It's a pronunciation thing β Italians never write the stress, you just have to know.
Four verbs at once
mangiare (to eat) β mangio, mangi, mangia, mangiamo, mangiate, mangiano. abitare (to live, to reside) β abito, abiti, abita, abitiamo, abitate, abitano. lavorare (to work) β lavoro, lavori, lavora, lavoriamo, lavorate, lavorano. comprare (to buy) β compro, compri, compra, compriamo, comprate, comprano. Same six endings every time.
The -care / -gare spelling rule
Verbs ending in -care or -gare keep the C and G hard everywhere β but the -i and -iamo endings would soften them. Solution: insert an H in writing. giocare (to play) β gioco, giochi, gioca, giochiamo, giocate, giocano. pagare (to pay) β pago, paghi, paga, paghiamo, pagate, pagano. The H has no sound β it just keeps the C or G hard before E and I.
The -iare drop
Verbs ending in -iare (like mangiare, studiare) already have an i in the stem. Italian doesn't double it β mangi, not mangii; mangiamo, not mangiiamo. The single i does double duty. studiare (to study) β studio, studi, studia, studiamo, studiate, studiano. Easy once you see it.
