Δεν μου αρέσει όταν κάποιος φωνάζει ή συμπεριφέρεται άσχημα στους άλλους.

In Greek, αρέσει works differently from English like.

• μου αρέσει literally means it is pleasing to me
• So the person who feels the emotion is in the form μου = to me
• The thing or action that is pleasing is the grammatical subject

In this sentence, the subject is the whole clause:

• όταν κάποιος φωνάζει ή συμπεριφέρεται άσχημα στους άλλους
  = when someone shouts or behaves badly toward others

So the structure is:

• Δεν μου αρέσει + [clause]
• literally: That does not please me

This is one of the most important patterns to learn in Greek.

Examples:

• Μου αρέσει ο καφές. = I like coffee.
• Μου αρέσει να διαβάζω. = I like reading.
• Δεν μου αρέσει όταν αργούν. = I don't like it when they are late.

μου means to me.

It is the weak form of the pronoun εγώ in an indirect-object function. With αρέσει, Greek uses this kind of pronoun because the meaning is literally is pleasing to me.

Compare:

• μου αρέσει = I like
• σου αρέσει = you like
• του αρέσει = he likes / he likes it
• της αρέσει = she likes
• μας αρέσει = we like
• σας αρέσει = you all like
• τους αρέσει = they like

So Δεν μου αρέσει is simply I don't like.

Because the thing that αρέσει is not a list of plural nouns. It is one whole idea:

όταν κάποιος φωνάζει ή συμπεριφέρεται άσχημα στους άλλους

A whole clause often acts like a single unit, so Greek uses singular αρέσει.

Compare:

• Μου αρέσει αυτό. = I like this.
• Μου αρέσει να ταξιδεύω. = I like traveling.
• Μου αρέσει όταν βρέχει. = I like it when it rains.

But with plural nouns, you get αρέσουν:

• Μου αρέσουν τα βιβλία. = I like books.

Greek often leaves subject pronouns out when they are not needed. This is very normal.

So instead of saying:

• Εγώ δεν μου αρέσει... ❌

Greek simply says:

• Δεν μου αρέσει... ✅

In fact, εγώ would usually only be added for emphasis or contrast, and even then this exact combination would not be the natural way to do it.

Greek is a pro-drop language, which means pronouns like I, you, he, she are often omitted because the verb form and the clitic pronouns already give enough information.

Here όταν can be understood as when or whenever, depending on context.

In this sentence, it has a general, repeated meaning:

• Δεν μου αρέσει όταν κάποιος φωνάζει...
• I don't like it when / whenever someone shouts...

So it is not talking about one specific moment only. It expresses a general reaction to that kind of behavior.

This is very common in Greek:

• Μου αρέσει όταν γελάς. = I like it when you laugh.
• Δεν μου αρέσει όταν μιλάνε έτσι. = I don't like it when they talk like that.

κάποιος means someone, somebody, or sometimes anyone depending on context.

Here it means a general someone/any person:

• όταν κάποιος φωνάζει = when someone shouts

It is in the masculine singular nominative form because it is the subject of φωνάζει and συμπεριφέρεται.

Important forms:

• κάποιος = someone, masculine
• κάποια = someone, feminine
• κάτι = something

Greek often uses the masculine form generically when the gender is unspecified, just as English can use someone without specifying gender.

Because both verbs refer back to κάποιος = someone.

So the structure is:

• κάποιος φωνάζει = someone shouts
• κάποιος συμπεριφέρεται = someone behaves

Since κάποιος is singular, the verbs are singular too.

Both are in the present tense, and here the present has a habitual or general meaning:

• when someone shouts or behaves badly not
• when someone is shouting right now

Because the verb is συμπεριφέρομαι, and it is one of those Greek verbs that commonly appears in the middle/passive form but has an active meaning.

So:

• συμπεριφέρομαι = I behave
• συμπεριφέρεται = he/she behaves

Even though the ending looks passive, the meaning here is not passive. It simply means behave.

This is something English speakers often notice in Greek. A lot of everyday verbs are like this.

Examples:

• φέρομαι καλά = I behave well
• συμπεριφέρεται άσχημα = he/she behaves badly

So just learn συμπεριφέρομαι as the normal dictionary form of behave.

φωνάζω can mean several related things:

• shout / yell
• call out
• sometimes call someone

In this sentence, the natural meaning is shouts or yells, because it is paired with bad behavior:

• όταν κάποιος φωνάζει ή συμπεριφέρεται άσχημα...

So the idea is clearly negative.

Examples:

• Μη φωνάζεις! = Don't shout!
• Με φώναξε από το παράθυρο. = He called to me from the window.
• Τη φωνάζουν Μαρία. = They call her Maria.

Context tells you which meaning is intended.

Because άσχημα is an adverb here, not an adjective.

It modifies the verb συμπεριφέρεται:

• συμπεριφέρεται άσχημα = behaves badly / behaves rudely

If you used άσχημος or another adjective form, it would describe a noun, not the action.

Compare:

• είναι άσχημος άνθρωπος = he is an ugly / unpleasant person
• συμπεριφέρεται άσχημα = he behaves badly

In this sentence, άσχημα is best understood as badly, poorly, or rudely, not literally ugly.

στους is a contraction of:

• σε + τους = στους

So:

• στους άλλους literally means to the others
• in natural English here: toward others or to other people

After σε, Greek uses the accusative, so:

• άλλους is masculine plural accusative
• τους is also masculine plural accusative article

This whole phrase depends on συμπεριφέρεται άσχημα:

• συμπεριφέρεται άσχημα στους άλλους
• behaves badly toward others

Very common contractions:

• σε τον → στον
• σε τη(ν) → στη(ν)
• σε το → στο
• σε τους → στους
• σε τις → στις
• σε τα → στα

It can absolutely mean others / other people in a general sense.

Although literally it contains the article τους, Greek often uses the article in places where English would not. So you should not always translate it word-for-word.

Here:

• στους άλλους = toward others / to other people

It does not have to mean a specific previously mentioned group of people. In a sentence like this, it sounds natural and general.

Yes, but it would not mean exactly the same thing.

Your original sentence:

• Δεν μου αρέσει όταν κάποιος φωνάζει ή συμπεριφέρεται άσχημα στους άλλους.

means:

• I don't like it when someone shouts or behaves badly toward others.

This describes your reaction to a situation in general.

If you say:

• Δεν μου αρέσει να φωνάζει...

that usually means:

• I don't like him/her shouting... or
• I don't like for someone to shout...

It can sound more specific depending on context, and the subject may need to be clearer.

So:

• όταν + clause = when/whenever this happens
• να + verb = to do something / doing something

Both are possible in Greek, but they are not interchangeable in every situation.

Greek word order is fairly flexible, but this version is the most neutral and natural.

Standard order here:

• Δεν μου αρέσει όταν κάποιος φωνάζει ή συμπεριφέρεται άσχημα στους άλλους.

You could move things for emphasis, but that changes the focus a little. For example:

• Όταν κάποιος φωνάζει ή συμπεριφέρεται άσχημα στους άλλους, δεν μου αρέσει.

This is possible, but it sounds more marked and less neutral in many contexts.

So for learners, the original order is the best one to use.