Learn Hardcore Malay: Dia mahu jelaskan mengapa dia kelihatan sombong, kerana sebenarnya dia sangat sensitif tentang kerja. - He/She wants to explain why he/she looks arrogant, because actually he/she is very sensitive about work.

Tadi dia mahu jelaskan... = Earlier he/she wanted to explain...
Esok dia mahu jelaskan... = Tomorrow he/she wants (will want) to explain...

So mahu itself is neutral for tense; context and time expressions carry the past/present/future meaning.

What is the difference between mahu jelaskan and mahu menjelaskan?

Both are understood as wants to explain, but there is a nuance:

menjelaskan = base jelas (clear) + prefix meN-
- suffix -kan
  → more standard/formal:
  Dia mahu menjelaskan... (very book‑ish / formal speech)
jelaskan (without meN-) often appears:
- after mahu, boleh, tidak akan, etc.
- in everyday / less formal language
  Dia mahu jelaskan... sounds more natural and conversational.

You can usually alternate them:

Dia mahu jelaskan mengapa...
Dia mahu menjelaskan mengapa...

Both are correct; the version with meN- just sounds slightly more formal.

What exactly does jelaskan mean? Is it closer to explain or make clear?

The root jelas means clear (understandable).

With -kan, jelaskan means to make something clear, which in normal English is simply to explain.

Typical patterns:

Jelaskan alasan kamu. = Explain your reason.
Boleh awak jelaskan lagi? = Can you explain (it) further?

You may also see terangkan / menerangkan with a very similar meaning. In this sentence, jelaskan is exactly explain.

What is the difference between mengapa and kenapa for why?

Both mengapa and kenapa mean why.

mengapa
- more formal / neutral
- common in writing, news, speeches, and polite conversation
kenapa
- more colloquial / everyday
- very common in casual spoken Malay

In this sentence, mengapa dia kelihatan sombong is slightly more formal than kenapa dia kelihatan sombong, but both are acceptable in speech. In many contexts you can freely switch between them.

What does kelihatan mean, and how is it different from nampak or tampak?

All three can relate to seeming/appearing or being seen:

kelihatan
- often seems / appears
- slightly more formal/neutral
- focuses on how something looks to others
Dia kelihatan sombong. = He/She appears arrogant.
nampak
- very common in everyday speech
- can mean to see or to look / seem
Dia nampak sombong. = He/She looks/comes across as arrogant.
tampak
- similar to kelihatan
- also sounds a bit literary or formal in some areas

In this sentence, kelihatan is like seems / appears and is a good neutral choice.

What does sombong really mean? Is it like proud or arrogant?

Sombong is strongly negative. It is closer to arrogant, stuck‑up, or snobbish.

Dia sombong. = He/She is arrogant / full of themselves.

If you want a more neutral or positive proud, Malay usually uses:

bangga = proud (in a good way)
Dia bangga dengan kerja dia. = He/She is proud of his/her work.

So in this sentence, kelihatan sombong means comes across as arrogant, not simply proud.

What is the difference between kerana and sebab for because?

Both can function as because, but there are some tendencies:

kerana
- conjunction because
- often slightly more formal / written
- used exactly like because
Dia marah kerana kamu lewat. = He/She is angry because you are late.
sebab
- can be a noun: reason
  - Apa sebabnya? = What is the reason?
- also commonly used as because in speech:
  - Dia marah sebab kamu lewat.

In many colloquial contexts, kerana and sebab as because are interchangeable. In your sentence, kerana fits well with the more neutral/formal tone created by mengapa, kelihatan, etc.

What is the function of sebenarnya here, and can it be moved to a different position?

Sebenarnya means actually, in fact, or really.
In this sentence:

kerana sebenarnya dia sangat sensitif tentang kerja
= because actually he/she is very sensitive about work

It softens or corrects the earlier impression, like:

He/She seems arrogant, but actually...

You can move sebenarnya for different emphasis:

Kerana dia sebenarnya sangat sensitif tentang kerja.
Kerana dia sangat sensitif tentang kerja sebenarnya.

All are grammatically fine. The version in the sentence puts sebenarnya early to highlight the contrast between appearing arrogant and actually being sensitive.

Why is tentang used in sensitif tentang kerja? Could other words be used instead?

Tentang here means about / regarding:

sensitif tentang kerja = sensitive about work

Other near‑synonyms:

mengenai = about, regarding (more formal)
berkenaan (dengan) = concerning, regarding
pasal = about (very informal/colloquial)

So you could say:

sensitif mengenai kerja (slightly more formal)
sensitif pasal kerja (very casual speech)

Tentang is a good neutral choice and very common in this pattern:
risau tentang..., marah tentang..., baca tentang..., etc.

Why is dia repeated three times? Can any of them be dropped?

The sentence has three clauses:

Dia mahu jelaskan...
mengapa dia kelihatan sombong,
kerana sebenarnya dia sangat sensitif tentang kerja.

Malay often repeats dia to keep each clause clear and avoid ambiguity, especially in careful or written style.

In casual speech, some speakers might drop a dia if the subject is obvious, for example:

Dia mahu jelaskan mengapa dia kelihatan sombong, kerana sebenarnya sangat sensitif tentang kerja.

This is understandable, but many speakers would still keep the last dia because the clause sebenarnya sangat sensitif tentang kerja sounds a bit bare without a subject.

So:

Repeating dia is completely normal and clear.
You can sometimes omit one in very casual speech, but for learners and for writing, keeping all three is safer.

Can the whole sentence be reordered, for example starting with the because part?

Yes. Malay word order is fairly flexible with clauses. You can front the reason:

Kerana sebenarnya dia sangat sensitif tentang kerja, dia mahu jelaskan mengapa dia kelihatan sombong.

This still means the same thing: you start with the because clause, then give the main clause.

Key points:

A comma is normally used after the fronted kerana‑clause.
You cannot break the internal order of each clause, e.g. you cannot say
Dia mahu jelaskan dia mengapa kelihatan sombong (wrong order).

So reordering full clauses is fine; reordering words inside a clause is much more limited.

How would this sentence sound in more casual, spoken Malay?

A natural colloquial version (especially in Malaysia) might be:

Dia nak jelaskan kenapa dia nampak sombong, sebab sebenarnya dia sangat sensitif pasal kerja.

Changes:

mahu → nak (very common spoken want to)
mengapa → kenapa (more everyday why)
kelihatan → nampak (common spoken looks / seems)
kerana → sebab (spoken because)
tentang → pasal (informal about)

The structure and meaning stay the same, but this version sounds much more like what friends might say in conversation.