Preterite vs Imperfect Spanish Grammar

Overview / Usage

One of the most challenging aspects of Spanish grammar is knowing when to use the preterite versus the imperfect tense. Both describe past actions, but they paint very different pictures of how those actions unfolded.

🎬 Think of it Like Movies

📸 Preterite = Snapshot
"I walked to school" (specific, completed action)
"She finished her homework" (definite beginning and end)

🎥 Imperfect = Video
"I was walking to school" (ongoing scene)
"She used to do homework" (habitual background)

Understanding this distinction will help you choose the right tense and communicate more precisely about past events.

Structure & Formation

⚖️ When to Use Each Tense

📸 Use Preterite For:

✅ Completed Actions

Ayer comí pizza

Yesterday I ate pizza

⏰ Specific Time/Duration

Estudié por tres horas

I studied for three hours

🔢 Sequence of Events

Llegué, abrí la puerta y entré

I arrived, opened the door and went in

🎥 Use Imperfect For:

🔄 Habitual Actions

Siempre comía pizza

I always used to eat pizza

⏳ Ongoing Actions

Estudiaba cuando llegaste

I was studying when you arrived

🖼️ Descriptions

La casa era grande y bonita

The house was big and beautiful

🔍 Signal Words That Help You Decide

📸 Preterite Signals

ayer (yesterday)
anoche (last night)
el año pasado (last year)
por tres horas (for three hours)
de repente (suddenly)
entonces (then)

🎥 Imperfect Signals

siempre (always)
todos los días (every day)
mientras (while)
cuando era niño (when I was a child)
generalmente (generally)
a menudo (often)

Examples

🎯 Side-by-Side Comparisons

See how the same situation can be expressed differently depending on your perspective:

Example 1: Eating

📸 Preterite (Completed Action)

Comí tacos ayer

I ate tacos yesterday

Focus: The eating happened and finished

🎥 Imperfect (Habitual Action)

Comía tacos todos los días

I used to eat tacos every day

Focus: The habit of eating tacos regularly

Example 2: Studying

📸 Preterite (Specific Duration)

Estudié por dos horas

I studied for two hours

Focus: Completed 2-hour study session

🎥 Imperfect (Ongoing Action)

Estudiaba cuando sonó el teléfono

I was studying when the phone rang

Focus: Ongoing studying interrupted by phone

Example 3: Mixed Story

🎬 Complete Story with Both Tenses

Context (Imperfect):Era una noche oscura

(It was a dark night)

Ongoing (Imperfect):Caminaba por el parque

(I was walking through the park)

Interruption (Preterite):De repente escuché un ruido

(Suddenly I heard a noise)

Completed Action (Preterite):Me volví y corrí a casa

(I turned around and ran home)

Gotchas / Common Mistakes

⚠️ Common Mistakes & Tricky Situations

❌ Mistake 1: Time Expressions

Wrong: Ayer comía pizza

Right: Ayer comí pizza

Why: "Ayer" (yesterday) indicates a specific completed time, so use preterite.

❌ Mistake 2: "Used to" Translation

Wrong: Usé vivir en Madrid

Right: Vivía en Madrid

Why: Spanish doesn't use "usar" for "used to" - just use imperfect directly.

❌ Mistake 3: Age and Time

Usually Imperfect: Tenía 10 años cuando... (I was 10 when...)

Sometimes Preterite: Cumplí 18 años ayer (I turned 18 yesterday)

Why: Age is usually ongoing state (imperfect), but birthdays are specific events (preterite).

🤔 Tricky: Same Verb, Different Meaning

conocer:

Preterite: Conocí a María ayer (I met María yesterday - first time)
Imperfect: Conocía a María (I knew María - ongoing knowledge)

saber:

Preterite: Supe la verdad (I found out the truth)
Imperfect: Sabía la verdad (I knew the truth)

Quick Test / Mini Quiz

Useful Resources

Coming soon...

Preterite vs Imperfect: When to Use Each