| Portuguese | Spanish |
|---|---|
| provar | probar |
| prOvo, prOva(m) | pruebo, prueba(n) |
| almoçar | almorzar |
| almOço, almOça(m) | almuerzo, almuerza(n) |
| mostrar | mostrar |
| mOstro, mOstra(m) | muestro, muestra(n) |
| negar | negar |
| nEgo, nEga(m) | niego, niega(n) |
| começar | comenzar |
| comEço, comEça(m) | comienzo, comienza(n) |
| nevar | nevar |
| nEva | nieva |
| chover | llover |
| chOve | llueve |
(In -ir verbs, these correspondences are observable only in 3rd person forms.)
| Portuguese | Spanish |
|---|---|
| preferir | preferir |
| prEfEre(m) | prefiere(n) |
| divertir | divertir |
| divErte(m) | divierte(n) |
| dormir | dormir |
| dOrme(m) | duerme(n) |
Notice below, however, that in verbs where the Spanish vowel-to-diphthong change is followed by an n in the same syllable, the Portuguese cognate is likely to have a nasal vowel instead of an open O or E. (Começar in the above list is an exception.) The verbs that follow are irregular in Spanish. Only sentir and mentir are irregular in Portuguese. (The irregularity is the nasal ĩ in the 1st person singular.)
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