Une petite dispute a commencé entre mon frère et ma sœur, puis mon frère a dit : « Pardon, je suis fatigué. »

Because dispute is a feminine singular noun in French.

So the words around it must agree with it:

• une = feminine singular a
• petite = feminine singular form of petit
• dispute = feminine singular noun

So:

• un petit problème
• une petite dispute

Also, une petite dispute often means a minor or small argument, not literally something physically small.

In French, many short, common adjectives often come before the noun, and petit / petite is one of them.

So:

• une petite dispute
• un petit livre
• une petite maison

If you put petite after the noun, it would sound unusual here. For a learner, the safest choice is to learn petit / petite as an adjective that very often comes before the noun.

a commencé is the passé composé, one of the main past tenses in French.

It is formed with:

• avoir in the present tense: a
• past participle: commencé

So:

• commencer → a commencé

In this sentence, the passé composé is used because the speaker is presenting the start of the argument as a completed event:

• A small argument started...

In everyday French, this is the most normal tense for that idea.

Because entre means between, and it is the natural word when two sides are involved.

So:

• entre mon frère et ma sœur = between my brother and my sister

You could sometimes use avec in other kinds of sentences, but here entre is the clearest and most natural choice because the dispute involved both people.

It repeats mon frère for clarity.

After mon frère et ma sœur have both been mentioned, if you say:

• puis il a dit

the listener may stop for a moment and think:

• Who is il? The brother or someone else?

So French often repeats the noun when there could be confusion:

• puis mon frère a dit

This is very natural and helps the sentence stay clear.

Because in normal modern French, the usual spoken past tense is the passé composé:

• a dit = said

French usually does not form this the way English does with a single past form like said. Instead, it uses:

• auxiliary verb: a
• past participle: dit

So:

• he said → il a dit

You may see dit by itself in literature, but that is usually the passé simple, a literary tense, not normal everyday spoken French.

Puis means then, after that, or next.

It links the two actions in sequence:

1. a small argument started
2. then the brother spoke

So puis is showing what happened next.

It is slightly more neutral or written-looking than et puis, but both are common.

That is standard French punctuation for introducing direct speech.

French often writes direct speech like this:

• Il a dit : « ... »

A few things to notice:

• the colon introduces what was said
• French often uses guillemets: « ... »
• in formal French typography, there is normally a space before the colon and spaces just inside the guillemets

English often uses regular quotation marks, but French commonly prefers « ... ».

Here, Pardon works like a short apology:

• Sorry
• Forgive me
• Excuse me

In this sentence, it sounds like:

• Sorry, I’m tired.

It is brief and direct. French could also use:

• Désolé
• Je suis désolé
• Excuse-moi

But Pardon is perfectly natural for a quick apology.

Because fatigué is an adjective, and French uses être with adjectives:

• je suis fatigué = I am tired

This is just like English in this case:

• I am tired
• je suis fatigué

So the pattern is:

• être + adjective

Examples:

• je suis content
• elle est malade
• nous sommes prêts

Yes.

The adjective must agree with the person speaking:

• male speaker: je suis fatigué
• female speaker: je suis fatiguée

That extra -e shows feminine agreement in writing.

In pronunciation, the two forms are usually pronounced the same, so the difference is mainly visible in spelling.

Because French possessive adjectives agree with the gender and number of the noun possessed, not with the owner.

So:

• frère is masculine → mon frère
• sœur is feminine → ma sœur

That is why the sentence has:

• mon frère
• ma sœur

Also notice that French normally repeats the possessive before each noun:

• mon frère et ma sœur

You would not normally leave the second one out here.

A rough English-friendly guide:

• frère ≈ frehr
• sœur ≈ a sound somewhat like sur, but with rounded lips; the œ sound does not exist exactly in English
• fatigué ≈ fa-tee-gay

A few extra notes:

• frère has an open è sound
• sœur contains the special spelling œ
• fatigué ends in -é, which sounds like ay

If you want to sound more natural, the hardest word here is usually sœur.