Past Simple: To Describe Completed Actions in the Past

What does "completed action" mean?

Imagine time as a line. Everything to the left is the past. Everything to the right is the future. Right in the middle is now — the present moment.

A completed action is an action that happened and finished at a specific point on the left side of that line. It is not connected to now. It is done. It is over. The moment it happened is fixed in time — like a photograph.

This is exactly what the Past Simple tense is for. You use it to describe a single event that was completed at a definite point in the past — whether that was five minutes ago or five hundred years ago.

How is the Past Simple formed?

Regular verbs — add -ed

Irregular verbs — must be memorised

Many common English verbs have irregular past forms. These do not follow the -ed rule. You must learn them individually. Examples: go → went, have → had, make → made, take → took, see → saw, say → said, write → wrote, build → built, fall → fell, win → won.

Affirmative sentences

Word order: Subject + past verb (+ rest of sentence)

There is no auxiliary verb in affirmative Past Simple sentences. The main verb carries all the tense information by changing its form. The word order is the same as Present Simple — you simply change the verb to its past form.

• She finished the report before the meeting started.
• They arrived at the airport two hours late.
• I called my mother as soon as I heard the news.
• He left the company in 2019 and never went back.
• My grandfather built this house with his own hands in 1952.

Negative sentences

Word order: Subject + did not (didn't) + base verb (+ rest of sentence)

To make a negative, you need the auxiliary verb did + not. This is called do-support. When you add did, the main verb goes back to its base form — it does NOT stay in the past form. Did carries the past tense; the main verb does not change.

• She didn't finish the report on time — she needed more time.
• They didn't arrive on time — the flight was delayed.
• I didn't call her back because I lost my phone.
• He didn't leave the company — he was promoted instead.
• We didn't visit the museum because it was closed.

Interrogative sentences (questions)

Word order: Did + subject + base verb (+ rest of sentence)?

To make a Yes/No question, move did to the front of the sentence before the subject. Again, the main verb returns to its base form — did carries the tense information.

For Wh- questions (What, Where, When, Why, How, Who), the question word comes first, then did, then the subject, then the base verb.

• Did you call her as soon as you heard?
• Did they arrive at the airport on time?
• Where did they go on holiday last summer?
• When did she graduate from university?
• What did your grandfather build in 1952?

When to use this tense — the logic of time

Think of the Past Simple for completed actions like a closed door. The action happened, the door opened, and then it closed again. The action is completely finished. Nothing about it continues into the present.

You always use this tense when you can answer the question "When did it happen?" with a specific time in the past — even if you don't say the time out loud. The time is known or implied.

Common time expressions that signal the Past Simple

Common mistakes to watch out for