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What’s the Past Tense of Swim? Swam vs. Swum

To swim is in the present tense. Swam is in the past tense, and had/have/has swum is the past participle.

What’s the past tense of “swim”?

Today’s lesson is on the past tense of swim—let’s dive right in!  

Verb forms of swim

To swim, defined by Collins Dictionary, is “to move through water by moving your arms and legs, without touching the bottom”. See the conjugations of swim below—

simpleI swimI swamI will swim
continuousI am swimmingI was swimmingI will be swimming
perfectI have swumI had swumI will have swum
perfect continuousI have been swimmingI had been swimmingI will have been swimming
12 verb tenses of ‘swim‘.

To swim is in the present tense:  How long will it take her to swim the Channel?

Swam is the simple past: The boys swam across the lake.

Swum is the past participle: I have swum in that pool before.

Irregular verbs like “swim”

base verbpast tensepast participle
Irregular verbs (two past tense conjugations).

When to use swam vs. swum

Read these sentences:

The boys swam across the lake. (past tense)

I have swum in that pool before. (past participle)

The past participle forms one of the perfect tenses, and also forms the passive voice, which uses a sentence object. Both the past participle and past tense of the verb swim (along with the past tenses of any verb) refer to actions or events that were completed entirely in the past. That’s a lot of information, and it helps to know certain ‘key terms’ in advance (it’s instructive to read the blog on verb tenses and participles before this one, in particular).  

The second sentence that shows the past participle also includes an auxiliary verb, have. Remove the auxiliary verb from the sentence, and it’s clear how participles require the use of an auxiliary/helping verb to function in sentences. This is because participles are based on verbs, and are not complete verbs that are capable of standing alone in sentences. Participles partake in the nature of a verb, and use auxiliary verbs.

Sentences with “swim” (present simple)

They are too far out to swim to shore.

I have always found it easy to swim underwater.

Can you swim backstroke yet?

How long will it take her to swim the Channel?

I can’t swim.

Sentences with “swam” (simple past)

The boys swam across the lake.

Exhausted, they swam ashore.

His head swam and he swayed dizzily.

He swam deeper into the lake.

He swam to an island that was not far away.

Sentences with “swum” (past participle)

I have swum in that pool before.

I had swum for only 15 minutes before it started to rain.

I’ve swum in these rivers, and they are unstable.

She has swum with sharks, sat on elephants, and ridden on dolphins.

As the only man on deck in the small hours, he sees that a man has swum up to the ship’s side.

Phrases with the word swim

sink or swim To succeed or fail quickly at something.
to be in the swim of things To be involved/knowledgeable on something.
faster than a minnow can swim a dipper To do something extremely quickly.
to swim against the current To go against the norm or conventions.
to swim with the tide or stream To go along with prevailing attitudes and sentiments.
to swim with the fishes Famously popularized by Mario Puzo, The Godfather. Meaning, to be dead.
Idioms with “swim”

Origin of the word swim

From etymology online on swim (v.):

Old English swimman “to move in or on the water, float” from Proto-Germanic *swimjan.


Other commonly confused verb tenses

Learn more about verbs


  1. Harper, Douglas. “Etymology of swim.” Online Etymology Dictionary, Accessed 16 January, 2023.
  2. “Swim.” 2023. Farlex, Inc. 16 Jan. 2023

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