Learn Hardcore Malay: Saya memakai jam tangan supaya saya tahu bila latihan renang bermula. - I wear a watch so that I know when the swim practice starts.

Memakai is the standard Malay verb meaning “to wear” (or “to use” in some contexts) formed by adding the prefix me- to the root pakai (“to wear/use”). In spoken Malay people often shorten it to pakai, but in written or more formal speech you use memakai to mark the verb clearly.

What does jam tangan mean, and why can’t I just say jam?

Jam tangan literally means “hand clock,” i.e. a wristwatch. Jam by itself means “hour,” “time,” or a general clock (like a wall clock). Saying jam tangan specifies the wearable watch.

Why is there a second saya in the sentence? Can I omit it?

Malay often repeats the subject for each clause: “Saya memakai … supaya saya tahu ….” You can drop the second saya in casual speech—“Saya memakai jam tangan supaya tahu bila latihan renang bermula”—and it’s still understood, but including it makes the subject of the subordinate clause clear.

What is supaya, and could I use untuk instead?

Supaya means “so that” or “in order that” and introduces a purpose/result clause with its own subject. You can also use untuk (“for/to”) plus an infinitive:
“Saya memakai jam tangan untuk mengetahui bila latihan renang bermula.”
Both are correct; supaya + a finite clause sounds more conversational.

Why is bila used here? What’s the difference between bila, apabila, and ketika?

All three can mean “when.” Bila is the most common in everyday speech and questions. Apabila is more formal or written. Ketika is literary or poetic and often used in formal writing to evoke a specific time.

Why is it latihan renang and not renang latihan?

Malay puts the main noun first and the modifier second. Latihan (“training”) is the head noun and renang (“swimming”) modifies it, so “swimming training” = latihan renang. Renang latihan would be unnatural.

What does bermula mean, and why the prefix ber-?

The root mula means “begin/start.” With the prefix ber-, it becomes an intransitive verb meaning “to begin” or “to start.” So latihan renang bermula = “swim training begins.” You could also say mula informally, but bermula is the standard form in this context.