In Spanish, just as in English, you can form past participles as adjectives, as long as you remember to match the number and gender of the noun that it’s modifying. This means that for plurals you have to add an extra s, and in the feminine form the -ado and -ido endings become -ada and -ida .
Past participles can be used as adjectives by following a few steps. You will look at your infinitive first, then you will drop the endings which are: “ar, er, ir, after dropping these endings, you add “ado or ido.” When you change a past participle into an adjective, it has to agree in number and gender with the noun.
For regular verbs ending in er, ir, you drop the “er, ir,: and add “ido.”
El juguete está roto. “roto” is your adjective that is in singular and masculine since “juguete,” is masculine.
The toy is broken
La ventana está rota. Here “rota,” is feminine and singular because ventana is feminine and there is only one.
The window is broken
Regular verbs end in “ar-er-ir,” and you make it into an adjective by dropping the “ar-er-ir,” and adding “ado” (-ar verbs) or “ido” (-er and -ir verbs).
Es tradición estar sentados a la mesa juntos toda la familia.
It is a tradition for the whole family to sit together at the table.
Regular Past Participles In Spanish
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| Verb Endings | Verbo Infinitivo | Participio pasado | Infinitive Verb | Past Participle |
| -AR = ADO(S) / ADA(S) | Jugar | Jugado | To play | Played |
| -IR = IDO(S) / IDA(S) | Vivir | Vivido | To live | Lived |
| -ER = IDO(S) / IDA(S) | Creer | Creído | To believe | Believed |
In some cases with a few verbs that end in “ir, er” such as leer, oír, you will drop the “er, ir,” and add “ído” with an accent.
Leer – leído
Oír – oído
Several Spanish verbs have irregular past participles: Some are: abrir – abierto; decir-dicho, hacer-hecho. There are several perfect tenses. They use the formula Haber + Past Participle. Example: Roberto ha viajado a Londres. Robert has traveled to London.
A regular Past Participle is a verb form that is usually used with Perfect Tenses. In English, the Past Participle is formed by either adding “-ed” or “-en” to the infinitive form, for example, the Past Participle of the verb “to walk” is “walked”.