هو كان زعلان، بس انبسط لما سمع نكتة من صديقه.

Yes, in many cases Arabic can leave out the subject pronoun because the verb already shows who is doing the action. But هو is often included in Levantine for clarity, emphasis, or just because it sounds natural in conversation.

So:

• كان زعلان = he was upset
• هو كان زعلان = also he was upset, but with the subject stated explicitly

In everyday speech, both are possible.

Because زعلان is an adjective, not a full verb. Literally, كان زعلان is something like he was upset / he was in an upset state.

This is very common in Arabic:

• كان تعبان = he was tired
• كانت مبسوطة = she was happy
• كان مشغول = he was busy

So كان gives the past meaning (was), and the adjective describes the state.

زعلان usually means upset, sad, annoyed, or bothered, depending on context. It is a very common everyday Levantine word.

It does not always mean deep sadness. It can describe anything from mild annoyance to emotional upset.

For example:

• أنا زعلان = I’m upset
• هي زعلانة = she’s upset

The feminine form is زعلانة.

بس here means but.

In Levantine, بس is extremely common in everyday speech. It can also mean only / just in other contexts, so the meaning depends on the sentence.

Here:

• هو كان زعلان، بس انبسط... = He was upset, but he became happy...

Compared with لكن, بس sounds more conversational and natural in spoken Levantine.

انبسط means he became happy, he cheered up, or he enjoyed himself, depending on context.

So the sentence shows a change of mood:

• first: كان زعلان = he was upset
• then: انبسط = he cheered up / became happy

This is why انبسط works well here: it shows that hearing the joke changed his emotional state.

In Levantine, ينبسط / انبسط is very common in speech.

لما here means when.

So:

• لما سمع نكتة = when he heard a joke

In Levantine, لما is a very common way to introduce a past-time clause. It is simple and natural in spoken language.

You will often see it in sentences like:

• لما وصل، اتصل فيي = when he arrived, he called me
• لما شافها، ضحك = when he saw her, he laughed

Usually it means when he heard, but in natural English the result can sound like after he heard because the second action follows the first one.

So in this sentence, the sense is:

• he was upset
• then he heard a joke
• then he cheered up

Because of that sequence, English might translate it as either when he heard or after he heard, depending on style. But لما itself is basically when.

سمع is the past tense, meaning he heard.

This is the basic past-tense verb form. In Levantine, short past verbs like this are very common:

• سمع = he heard
• شاف = he saw
• عرف = he knew / found out
• ضحك = he laughed

So لما سمع نكتة literally means when he heard a joke.

Arabic normally does not have a separate word for the indefinite article a/an.

So:

• نكتة can mean a joke
• النكتة means the joke

This is very important in Arabic:

• no الـ = usually indefinite
• with الـ = definite

So سمع نكتة = he heard a joke, not the joke.

Because نكتة is a feminine noun, and many feminine nouns in Arabic end in ـة.

So:

• نكتة = joke
• it is grammatically feminine

That does not change much in this sentence, because nothing here has to agree with it in an obvious way. But it matters in other sentences, for example with adjectives or pronouns.

It means from his friend.

Here, من shows the source of the joke:

• سمع نكتة من صديقه = he heard a joke from his friend

In natural English, we might also say he heard a joke from his friend or his friend told him a joke.

So من is working like from.

Because Arabic often shows possession by attaching a pronoun suffix directly to the noun.

Here:

• صديق = friend
• صديقه = his friend

The ـه ending means his.

This is very common:

• بيته = his house
• اسمه = his name
• كتابه = his book

In Levantine pronunciation, صديقه is often pronounced roughly like ṣadīʔo.

It is correct, but in casual Levantine, speakers also often use words like صاحب or رفيق, depending on region and style.

So:

• صديقه = his friend
• صاحبه = his friend
• رفيقه = his friend

All are possible, but صديق is clear and widely understood. It can sound a little more neutral or slightly more formal than some everyday alternatives.

Because in spoken Levantine, subject-first order is very common and natural.

So:

• هو كان زعلان = very natural in conversation
• كان زعلان = also natural
• كان هو زعلان = possible, but different in emphasis

Levantine often prefers a straightforward conversational structure, especially in simple narrative sentences.

A common Levantine-style pronunciation would be roughly:

huwwe kān zaʿlān, bas inbasaṭ lamma semiʿ nikte mn ṣadīʔo

A few notes:

• هو is often pronounced huwwe
• بس sounds like bas
• انبسط is often inbasaṭ
• لما sounds like lamma
• نكتة is often nikte
• صديقه may sound like ṣadīʔo

Exact pronunciation varies by country and city, but this is a helpful general Levantine approximation.