Learn Hardcore Malay: Saya berjalan di kiri jalan untuk mengelak bas yang laju. - I walk on the left side of the road to avoid the fast bus.

Past: tadi, semalam, telah/sudah (formal) — e.g., Tadi saya berjalan...
Present progressive: sedang — Saya sedang berjalan...
Future: akan — Saya akan berjalan...

Why use berjalan instead of just jalan as a verb?

berjalan is the standard verb meaning to walk.
jalan is a noun meaning road/street. In colloquial speech, people sometimes say Saya jalan to mean I walk, but in standard Malay you use berjalan for the action.
The sentence uses both senses: berjalan (to walk) and jalan (road).

What exactly does di kiri jalan mean? Whose left is it?

Di kiri jalan means on the left side of the road, typically from the perspective of someone moving along that road in that direction. It does not refer to the road’s north/west, but to the left-hand side relative to the direction of travel or viewpoint.

Is there a difference between di kiri jalan and di sebelah kiri jalan?

They’re functionally the same. Sebelah literally means side, so di sebelah kiri jalan is a bit more explicit. Both are natural:

Saya berjalan di kiri jalan...
Saya berjalan di sebelah kiri jalan...

Could I say di tepi jalan instead?

Di tepi jalan means at/by the roadside (the edge). If you specifically mean the left side, keep kiri:

Left side in general: di kiri jalan / di sebelah kiri jalan
At the roadside/shoulder: di tepi jalan or di bahu jalan

Is mengelak the right verb here? What about mengelakkan or menghindari?

mengelak = to dodge/avoid (often physical or immediate), e.g., mengelak bas.
mengelakkan = to avoid or to prevent something from happening; commonly used with undesirable outcomes, e.g., mengelakkan kemalangan (to prevent/avoid accidents), or with reflexive phrase mengelakkan diri.
menghindari (more formal/literary) = to avoid, steer clear of, e.g., menghindari masalah.

In this sentence, untuk mengelak bas yang laju (to avoid a fast bus) is natural. You could also recast the idea as ...untuk mengelakkan kemalangan (to avoid an accident).

Should it be mengelak bas or mengelak daripada bas?

Both occur, but usage differs:

Direct object is common and natural with concrete things: mengelak bas (avoid/dodge the bus).
mengelak daripada is more common with events or VPs: mengelak daripada dilanggar (avoid being hit). Using dari instead of daripada is widespread in speech, but in careful Malay prefer daripada for this function.

Why is it bas yang laju and not just bas laju?

bas laju = a fast bus (adjective directly after the noun; general property).
bas yang laju = the bus that is fast (a relative clause with yang; often more specific or descriptive of the current situation).

In context, bas yang laju can sound like a particular bus that was going fast at that moment, which fits the sentence’s event reading. You can also say bas laju; it’s natural too. The nuance is about specificity/emphasis, not grammaticality.

Do I always need yang before adjectives?

No. The default is noun + adjective with no linker:

bas besar, bas merah, bas laju

Use yang when:

You form a fuller relative clause: bas yang saya nampak
You want to emphasize/clarify: bas yang laju itu
The modifier is long/complex

How do I say the bus vs a bus in Malay?

Malay has no articles. Definiteness is inferred from context or added with determiners/classifiers:

A bus: sebuah bas (one bus; optional), or just bas in context.
The bus: bas itu (that bus), bas tadi (the earlier bus), bas tersebut (the said bus; formal).

So your sentence could be:

...mengelak sebuah bas yang laju (to avoid a fast bus)
...mengelak bas laju itu (to avoid that fast bus)

Is laju the same as cepat or pantas?

laju = fast in terms of speed/velocity (vehicles, movement): bas laju, lari laju
cepat = quick/soon/early, focuses on time or promptness: Datang cepat!
pantas = swift/nimble/efficient (more formal or elevated style)

Here laju is the best fit for a moving vehicle.

Can I move the untuk clause elsewhere in the sentence?

Yes. Purpose phrases with untuk are mobile, as long as the meaning stays clear:

Saya berjalan di kiri jalan untuk mengelak bas yang laju.
Untuk mengelak bas yang laju, saya berjalan di kiri jalan.
Saya, untuk mengelak bas yang laju, berjalan di kiri jalan. (less common; adds emphasis)

Is untuk elak acceptable, or must it be untuk mengelak?

In careful/standard Malay, use the meN- form after untuk when the verb is lexical: untuk mengelak. In casual speech you’ll hear untuk elak, but it’s less formal.

Could I say this with supaya or agar instead of untuk?

Yes, but the structure changes. Supaya/agar introduces a full clause with a subject:

Purpose with untuk + V: Saya berjalan di kiri jalan untuk mengelak bas...
Purpose with supaya/agar + clause: Saya berjalan di kiri jalan supaya saya tidak dilanggar oleh bas yang laju. The supaya/agar version often states the desired outcome explicitly (not being hit).

Is bas the standard word? I’ve seen bus or bis.

In Malay (Malaysia/Brunei), the standard is bas. In Indonesian, bus is standard and bis is also seen. Stick with bas in Malay.

Can I drop the subject Saya?

You can in instructions/signage or when context is crystal clear:

Instructional sign: Berjalan di kiri jalan untuk mengelak bas yang laju. But for a normal declarative sentence about yourself, keep Saya to avoid ambiguity.

Any nuance difference if I say jalan raya instead of jalan?

jalan = road/street generally.
jalan raya = main road/highway (larger/major road). If you mean a generic road, jalan is fine. If you want to stress it’s a main road, use jalan raya: ...di kiri jalan raya...

How do I pronounce mengelak and laju?

Approximate pronunciations:

mengelak: muhng-uh-lak (the ng is as in singer; final k is unreleased)
laju: lah-joo
bas: bahs (short a)