Spanish Past Tenses.Pretérito Perfecto, Indefinido & Imperfecto.

Choosing between Pretérito Perfecto, Indefinido, and Imperfecto can be challenging due to the nuance each tense conveys about the action and its context. Here are some guidelines and examples to help you make the right choice:

• Pretérito Perfecto is often used for actions that have a connection to the present. Signal words that commonly accompany this tense include hoy (today), esta semana (this week), este año (this year), alguna vez (ever), nunca (never), ya (already), todavía (still/yet).
  • Hoy he comido pizza. (Today I have eaten pizza.)
  • Este año hemos viajado a México. (This year we have traveled to Mexico.)
• Indefinido is typically used for actions that are viewed as completed with no relation to the present. Signal words include ayer (yesterday), la semana pasada (last week), el año pasado (last year), anoche (last night), hace un mes (a month ago).
  • Ayer fui al cine. (Yesterday I went to the cinema.)
  • El año pasado estudié en Madrid. (Last year I studied in Madrid.)
• Imperfecto is used for habitual actions in the past, descriptions, or actions without a defined endpoint. Common signal words include siempre (always), todos los días (every day), mientras (while), de niño (as a child), antes (before).
  • De niño jugaba con mis primos todos los días. (As a child, I played with my cousins every day.)
  • Mientras trabajaba en la oficina, escuchaba la radio. (While I was working in the office, I listened to the radio.)

The choice of tense often depends on subtle nuances:

• Context: Consider the context and whether the action has relevance to the present, is seen as completed, or describes a habitual or ongoing past action.
• Time markers: Pay attention to time markers or signal words to determine the correct tense.
• Nuances: Small details in the context can influence the choice of tense. For instance, estuve todo el día en casa (I was home all day) indicates a completed action with a defined period, whereas estaba en casa todo el día (I was home all day) suggests a habitual action or an action in progress.

The conjugation of regular verbs in different tenses such as Pretérito Perfecto, Indefinido, and Imperfecto can be systematized by following specific endings for -ar, -er, and -ir verbs.

For the Pretérito Perfecto tense:

• To form the Pretérito Perfecto, use the present tense of the auxiliary verb haber followed by the past participle of the main verb.
• The formation of the past participle involves changing the -ar ending to -ado and both -er and -ir endings to -ido.

For the Indefinido tense:

• For -ar verbs, use the endings: -é, -aste, -ó, -amos, -asteis, -aron.
• For -er verbs, use the endings: -í, -iste, -ió, -imos, -isteis, -ieron.
• For -ir verbs, use the same endings as -er verbs: -í, -iste, -ió, -imos, -isteis, -ieron.

Subject	-ar verbs (hablar)	-er verbs (comer)	-ir verbs (vivir)
yo	hablé	comí	viví
tú	hablaste	comiste	viviste
él/ella/usted	habló	comió	vivió
nosotros/nosotras	hablamos	comimos	vivimos
vosotros/vosotras	hablasteis	comisteis	vivisteis
ellos/ellas/ustedes	hablaron	comieron	vivieron

For the Imperfecto tense:

• For -ar verbs, use the endings: -aba, -abas, -aba, -ábamos, -abais, -aban.
• For -er and -ir verbs, use the endings: -ía, -ías, -ía, -íamos, -íais, -ían.

Subject	-ar verbs (hablar)	-er verbs (comer)	-ir verbs (vivir)
yo	hablaba	comía	vivía
tú	hablabas	comías	vivías
él/ella/usted	hablaba	comía	vivía
nosotros/nosotras	hablábamos	comíamos	vivíamos
vosotros/vosotras	hablabais	comíais	vivíais
ellos/ellas/ustedes	hablaban	comían	vivían

Common Mistakes and How to Avoid Them:

• Confusing Pretérito Perfecto and Pretérito Indefinido:
  • Incorrect: He hablado con ella ayer.
  • Correct: Hablé con ella ayer.
  • Explanation: Pretérito Perfecto is used for actions tied to the present, while Pretérito Indefinido is used for completed actions in the past with no present relevance.
  • Tip: Use mnemonic devices like "He has spoken" to remember that Pretérito Perfecto connects to the present and "He spoke" for actions that are completely in the past.
• Using Pretérito Imperfecto for Completed Actions:
  • Incorrect: Cuando era niño, nadaba en el lago ayer.
  • Correct: Cuando era niño, nadé en el lago ayer.
  • Explanation: Pretérito Imperfecto describes habitual or ongoing past actions, not specific completed events.
  • Tip: Remember "used to" for Pretérito Imperfecto to signify habitual actions: "I used to swim."
• Mixing up Time Markers:
  • Incorrect: El año pasado he vivido en España.
  • Correct: El año pasado viví en España.
  • Explanation: Time markers like "ayer" or "el año pasado" indicate a specific time, which requires Pretérito Indefinido.
  • Tip: Common time markers for different tenses: hoy (Pretérito Perfecto), ayer (Pretérito Indefinido).