Selepas terjatuh dari basikal, dia ada calar kecil di dagu dan lengan kirinya.

Selepas means after.

In this sentence, selepas terjatuh dari basikal means after falling off the bicycle.

A useful pattern is:

• selepas + noun = after + noun
• selepas + verb/clause = after + doing something / after something happens

Examples:

• selepas makan = after eating
• selepas kelas = after class
• selepas dia sampai = after he/she arrived

Here, selepas introduces the event that happened first.

Jatuh means to fall.

Terjatuh usually suggests that the fall happened accidentally or unintentionally. That makes it very natural here, because falling off a bicycle is normally not deliberate.

So:

• jatuh = fall
• terjatuh = accidentally fall / end up falling

In many contexts, English will translate both simply as fell, but ter- adds the idea that it was not intentional.

Malay often leaves out a subject when it is already clear from context.

So:

• Selepas terjatuh dari basikal, dia...
  = After falling off the bicycle, he/she...

The understood subject of terjatuh is the same dia in the main clause.

You could also say:

• Selepas dia terjatuh dari basikal, dia ada...

But that sounds more repetitive. The version in your sentence is smoother and very natural.

Here dari is used because it refers to movement from a place or position.

In terjatuh dari basikal, the idea is falling from/off the bicycle.

A common guideline is:

• dari = from a place, direction, or location
• daripada = from a person/source, than, made of

Examples:

• dari sekolah = from school
• dari atas meja = from the top of the table
• daripada Ali = from Ali
• lebih besar daripada... = bigger than...

So dari basikal is the correct choice here.

Yes. In this sentence, ada is being used in the sense of has.

So:

• dia ada calar kecil = he/she has a small scratch

This is very common in everyday Malay, especially when talking about injuries, features, or things someone has.

Examples:

• dia ada kereta = he/she has a car
• saya ada masalah = I have a problem
• dia ada luka di tangan = he/she has a wound on the hand

More formal Malay might use mempunyai, but ada is much more common in normal speech.

In Malay, adjectives usually come after the noun.

So:

• calar kecil = small scratch
• rumah besar = big house
• buku lama = old book

That is the normal word order:

• noun + adjective

So calar kecil is the expected pattern.

Di marks location, and in English its best translation depends on context.

With body parts, English may use on, but Malay still commonly uses di:

• di dagu = on the chin
• di tangan = on the hand / at the hand area
• di kaki = on the leg / foot

So di is not limited to just in. It can correspond to in, at, or on depending on what sounds natural in English.

Because the single di can apply to both parts of the coordinated phrase.

So:

• di dagu dan lengan kirinya

means:

• on the chin and his/her left arm

Malay often avoids repeating the same preposition when one preposition clearly covers both nouns.

You could also say:

• di dagu dan di lengan kirinya

That is also grammatical, but repeating di is not necessary here.

Lengan kirinya means his/her left arm.

Breakdown:

• lengan = arm
• kiri = left
• -nya = his/her, or sometimes a marker making something definite

So the structure is:

• lengan kiri = left arm
• lengan kirinya = his/her left arm

This is a common Malay pattern:

• noun + adjective + possessor

Examples:

• tangan kanannya = his/her right hand
• mata kirinya = his/her left eye

You could also say lengan kiri dia, but lengan kirinya is very natural and compact.

It can mean either he or she.

Malay does not usually mark gender in third-person singular pronouns the way English does.

So:

• dia = he / she

You only know which one is meant from context.

The same is true for -nya in kirinya:

• it can mean his or her

Malay does not use articles like a or the in the same way English does.

So calar kecil can naturally be translated as a small scratch here.

In context, it sounds singular, but Malay nouns often do not have to be marked for singular/plural unless needed.

If you wanted to make plurality clearer, you could say:

• calar-calar kecil = small scratches
• beberapa calar kecil = several small scratches

So the sentence leaves that to context, which is very normal in Malay.