Learn Hardcore Malay: Kalau saya lupa guna seterika, kemeja saya penuh kedut dan kelihatan tidak kemas. - If I forget to use the iron, my shirt is full of wrinkles and looks untidy.

kalau – very common in speech, informal or neutral writing; used for conditions and “if/when”-type situations.
jika – more formal; often used in writing, instructions, official notices.
bila – often means when, but in colloquial Malay it can also act like if (context decides).

In this sentence you could say:

Jika saya lupa guna seterika, … (more formal)
Bila saya lupa guna seterika, … (more colloquial)

All are understandable, but kalau is a very natural, everyday choice.

Why is there no word for then in the second part, like “If I forget…, then my shirt is…”?

Malay usually doesn’t need an explicit then in conditionals. The structure:

Kalau X, Y.

already implies If X, (then) Y.

You can add a word like maka or jadi for emphasis or in more formal / narrative styles:

Kalau saya lupa guna seterika, maka kemeja saya penuh kedut… (very formal / written)
Kalau saya lupa guna seterika, jadi kemeja saya penuh kedut… (colloquial, more like “so/therefore”)

But in normal everyday Malay, the sentence is most natural without a word for then.

Why is it lupa guna and not lupa untuk guna? Is lupa untuk wrong?

Lupa guna literally is forget use, and this is perfectly natural Malay.

lupa guna seterika = forget to use the iron

You can say lupa untuk guna seterika, and it is grammatically acceptable, but:

lupa guna is shorter and more natural in everyday speech.
lupa untuk sounds a bit more formal or deliberate, and is used more often with longer, more “serious” actions (e.g. lupa untuk membayar bil – forgot to pay the bill).

So here, lupa guna is the most idiomatic choice.

What is the difference between guna and menggunakan? Could I say lupa menggunakan seterika?

Both come from the same root meaning to use:

guna – base verb, very common and neutral.
menggunakan – longer, meN--form of the verb; slightly more formal / careful.

In this sentence, all of these are possible:

lupa guna seterika
lupa gunakan seterika
lupa menggunakan seterika

Differences:

In everyday speech, guna is the most natural and common.
menggunakan sounds a bit more formal, like written Malay, instructions, or careful speech.
gunakan is the meN- form with a direct object (here, seterika).

So yes, lupa menggunakan seterika is correct, just more formal-sounding than lupa guna seterika.

Is seterika a noun (iron) or a verb (to iron)? How do Malays usually say “to iron (clothes)”?

Seterika is primarily a noun: an iron (the appliance).

In everyday usage:

People often say seterika baju to mean iron (the) shirt/clothes, where seterika behaves like a verb in context.
A very common verb phrase is gosok baju = iron clothes (literally “rub clothes”).

More formal verb forms exist:

menseterika baju / menyeterika baju – “to iron clothes” (using the meN- verb form), but these are less common in casual speech.

So, in daily conversation you mostly hear:

Saya nak seterika baju. (I want to iron my clothes.)
Saya nak gosok baju. (same meaning)

What does penuh kedut literally mean, and could you just say berkedut instead?

Literally:

penuh = full (of)
kedut = wrinkles

So penuh kedut = full of wrinkles, i.e. very wrinkly / really creased.

You can use berkedut:

kemeja saya berkedut = my shirt is wrinkled / creased

Nuance:

penuh kedut is more visual and emphatic: covered in wrinkles, full of creases.
berkedut is more neutral: wrinkled, without the “full of” emphasis.

The sentence uses penuh kedut to stress how bad the wrinkles are.

What is the difference between kedut and kedutan?

Both relate to wrinkles, but they’re used slightly differently.

kedut
- Can act as a noun: wrinkle / crease
- Often appears in set phrases like penuh kedut (full of wrinkles).
kedutan
- A noun formed with -an, often meaning a wrinkling / wrinkles as a general condition.
- Common in phrases like banyak kedutan (many wrinkles), e.g. on skin or clothes.

In this sentence:

penuh kedut is the common, idiomatic phrase.
You could say penuh kedutan, but it’s less common and sounds more formal or descriptive.

What exactly does kelihatan mean, and how does it differ from nampak or terlihat?

All three relate to appearing / seeming / being seen, but with different tones:

kelihatan
- Often translated as looks / appears.
- Slightly more neutral or formal.
- Used for how something appears to the eye.
- kelihatan tidak kemas = looks untidy.
nampak
- Very common in spoken Malay.
- Can mean to see (saya nampak dia = I see him/her) or to look / to seem (nampak penat = looks tired).
- Informal compared to kelihatan.
terlihat
- More literally “to be seen / to be visible”, or “happened to see”.
- Less common in everyday speech in this exact function; more literary or specific contexts.

You could say:

kemeja saya nampak tidak kemas (more colloquial)
kemeja saya kelihatan tidak kemas (neutral, maybe a bit more careful/formal)

Both are fine; kelihatan fits well in a neutral written example sentence.

What does tidak kemas really mean? Is it just “messy”, and when would you use tidak vs tak?

Meaning:

kemas = tidy, neat, orderly.
tidak kemas = not tidy → untidy / messy / sloppy-looking.

So kelihatan tidak kemas ≈ looks untidy / looks messy.

About tidak vs tak:

tidak – standard form; suitable in writing, formal speech, and also fine in everyday conversation.
tak – informal, shortened version used heavily in spoken Malay.

In speech you will often hear:

kelihatan tak kemas or nampak tak kemas.

In a neutral example sentence like this, tidak kemas is a good choice.

There’s no tense marking here. How do we know if it means “If I forget”, “If I forgot”, or “When I forget”?

Malay verbs usually do not change form for tense. Context supplies time.

The clause Kalau saya lupa guna seterika can cover several English possibilities:

If I forget to use the iron (general habit / future possibility)
When I forget to use the iron (repeated habit)
In the right story context, even If I forgot to use the iron (in the past), though that’s less likely without extra markers.

To be more explicit, Malay can add time words:

Kalau nanti saya lupa guna seterika… (If I later / if I end up forgetting… → future)
Kalau dulu saya lupa guna seterika… (If in the past I forgot to use the iron…)

Here, with no markers, the natural reading is a general or habitual condition: whenever / if I (ever) forget, my shirt ends up wrinkled.

Why is saya used twice? Could you say Kalau saya lupa guna seterika, kemeja penuh kedut…?

Yes, you can drop the second saya:

Kalau saya lupa guna seterika, kemeja penuh kedut dan kelihatan tidak kemas.

Malay often drops repeated pronouns when it’s clear who you mean.

Using saya again (kemeja saya) is also correct and natural; it just:

Emphasizes a bit more that it’s my shirt, not someone else’s.
Sounds slightly more complete and clear in an isolated example sentence.

In everyday conversation, both versions are fine.

Why is kemeja saya penuh kedut dan kelihatan tidak kemas in that order? Could I switch the two descriptions?

Yes, you can switch them:

kemeja saya penuh kedut dan kelihatan tidak kemas
kemeja saya kelihatan tidak kemas dan penuh kedut

Both are grammatically fine.

Subtle nuance:

Original: first gives the physical state (full of wrinkles), then the overall impression (looks untidy).
Switched: first gives the impression (looks untidy), then adds a reason/detail (and is full of wrinkles).

In normal speech, both word orders would be easily understood and acceptable.