Learn Hardcore Malay: Doktor mata menasihatkan saya supaya rehatkan mata setiap setengah jam. - The eye doctor advises me to rest my eyes every half hour.

pakar mata – eye specialist (more formal; pakar = specialist)
doktor pakar mata – eye specialist doctor
doktor oftalmologi – ophthalmologist (very technical; rarely used in casual speech)

In this sentence, Doktor mata menasihatkan saya… sounds perfectly natural.

Why is menasihatkan used here instead of menasihati or just nasihat?

Base word: nasihat = advice

Two common verb forms:

menasihatkan
- Pattern: meN- + nasihat + -kan
- Often used when the thing being given is advice.
- Rough meaning: “to give advice (to someone)”
- Example:
  - Doktor mata menasihatkan saya supaya...
    = The eye doctor advised me to...
menasihati
- Pattern: meN- + nasihat + -i
- Often used when the person being advised is the focus.
- Rough meaning: “to advise someone / to admonish someone”
- Example:
  - Doktor mata menasihati saya supaya...
    = The eye doctor advised me so that...

In modern usage, menasihatkan and menasihati often overlap, and many native speakers don’t feel a strong difference in everyday speech. Both would be understood and acceptable here.

Using just nasihat as a verb (without me-) is not standard; as a verb you normally use menasihatkan or menasihati.

What does supaya do in this sentence? Could we leave it out or replace it?

In this sentence:

Doktor mata menasihatkan saya supaya rehatkan mata setiap setengah jam.

supaya introduces the content or purpose of the advice, similar to:

“to…”, “so that…”, “in order to…”

So the structure is:

menasihatkan saya supaya [clause]
= advised me to [do something]

Here, the clause after supaya is rehatkan mata setiap setengah jam.

Alternatives:

agar – almost the same meaning; a bit more formal/literary
- …menasihatkan saya agar rehatkan mata…
In many everyday sentences you can drop supaya/agar:
- Doktor mata menasihatkan saya rehatkan mata setiap setengah jam.
  (Still understandable, but some speakers feel it’s smoother with supaya here.)

So supaya is not 100% mandatory, but it is natural and helps clearly mark the clause that follows as the “thing you should do”.

Why is it rehatkan mata and not berehat mata? What’s the difference between rehatkan and berehat?

Base word: rehat = rest

Two common verb forms:

berehat
- Intransitive verb (no direct object).
- Means “to rest (oneself)”.
- Example:
  - Saya perlu berehat. = I need to rest.
rehatkan
- Verb with -kan; can take an object.
- Means “to rest (something)”, “to cause something to rest”.
- Example:
  - rehatkan mata = rest (your) eyes
  - rehatkan badan = rest (your) body

In the sentence:

…supaya rehatkan mata setiap setengah jam.

The idea is “rest (your) eyes”, so Malay uses rehatkan mata (rest something) rather than berehat mata, which would sound ungrammatical.

Alternative phrasing:

supaya mata saya boleh berehat setiap setengah jam
= so that my eyes can rest every half hour

Here you turn the eyes into the subject of berehat.

What does setiap setengah jam mean exactly, and is the word order fixed?

setiap setengah jam breaks down like this:

setiap = every / each
setengah = half
jam = hour

So it literally means “every half hour”.

Word order is fixed: setiap + setengah + jam. You would not say setengah setiap jam here.

Compare:

setiap tiga jam = every three hours
setiap lima minit = every five minutes
setiap setengah jam = every half hour

Be careful:

setengah jam = half an hour (30 minutes)
jam setengah (in telling time, e.g. jam setengah tiga) is more like “half to three” (2:30), and is a different structure related to clock time, not intervals.

Could we say setiap tiga puluh minit instead of setengah jam? Is there any difference?

Yes, you can. Both are correct:

setiap setengah jam = every half hour
setiap tiga puluh minit = every thirty minutes

Meaning-wise, they’re the same (30-minute interval).

Nuance:

setengah jam sounds a bit more casual/natural in everyday speech.
tiga puluh minit is more explicit, a bit more “counting-style”, which some doctors or instructions might prefer if they want to avoid any ambiguity.

But in normal conversation, setiap setengah jam is very common.

There’s no past tense marker. How do we know this is “advised” (past) and not “is advising” (present)?

Malay usually does not mark tense with verb endings. menasihatkan doesn’t show past, present, or future directly. The time is understood from:

context (what you already know about the situation)
time words if needed (e.g. tadi, semalam, esok).

Your English translation is:

The eye doctor advised me to rest my eyes every half hour.

In Malay, this same sentence could also be interpreted as describing a habitual situation, depending on context.

If you want to be very clear about the time, you add a time word:

Doktor mata tadi menasihatkan saya…
= Earlier, the eye doctor advised me…
Semalam doktor mata menasihatkan saya…
= Yesterday the eye doctor advised me…

So the lack of tense marking is normal; Malay relies heavily on context and time adverbs.

Can we leave out saya? Would Doktor mata menasihatkan supaya rehatkan mata… still be correct?

Yes, you can drop saya, and it will still be grammatically correct:

Doktor mata menasihatkan supaya rehatkan mata setiap setengah jam.

Malay is quite flexible about pronouns when the subject/object is obvious from context.

However, note the nuance:

Doktor mata menasihatkan saya supaya…
Explicitly: advised me.
Doktor mata menasihatkan supaya…
More general: advised (people/you) to… – could be “advised me”, “advised us”, “advised patients”, depending on context.

If you want to be clear that the advice was directed specifically at you, keeping saya is best.

What’s the difference between menasihatkan saya supaya… and suruh saya…?

Both can translate to “told me to / asked me to”, but the tone is different.

menasihatkan saya supaya…
- More formal, polite, and gentle.
- Emphasizes that it is advice or a recommendation.
- Fits very well with professionals (doctors, teachers, etc.).
suruh saya…
- More direct; like “told me to / ordered me to”.
- Can sound a bit stronger or more commanding.
- Common in everyday speech.

Example informal version:

Doktor mata suruh saya rehatkan mata setiap setengah jam.
= The eye doctor told me to rest my eyes every half hour.

This is natural in casual conversation and doesn’t necessarily sound rude; tone of voice and context matter a lot.

Why isn’t there itu after doktor mata, like Doktor mata itu…? When would we use itu or ini?

itu = that / the
ini = this

You can add them for specificity:

doktor mata itu = that eye doctor / the eye doctor (already known)
doktor mata ini = this eye doctor (near me / just mentioned)

In the sentence given:

Doktor mata menasihatkan saya…

Without ini/itu, it just means “the eye doctor” in a general sense, and context usually makes it clear which one you mean (e.g., the one you were just talking about).

Using itu:

Doktor mata itu menasihatkan saya…
= That (particular) eye doctor advised me…

You’d use itu if you want to point to a specific doctor you and the listener both already know or can see. Without it, it’s a bit more neutral/generic.

Could this sentence be made more casual? What would a more colloquial version look like?

Yes. A more casual, conversational version might be:

Doktor mata suruh saya rehatkan mata tiap setengah jam.

Changes:

menasihatkan → suruh (told me to)
setiap → tiap (shorter, everyday form)

Even more colloquial (depending on region and familiarity):

Doktor mata cakap saya kena rehatkan mata tiap setengah jam.
- cakap = say
- kena here = have to / must

All of these are understandable. The original sentence is slightly more formal / neutral, suitable for writing or polite conversation.

How would this sentence change if the doctor advised someone else instead of me?

You mainly change the pronoun saya to another pronoun or name:

Doktor mata menasihatkan dia supaya rehatkan mata setiap setengah jam.
= The eye doctor advised him/her to rest his/her eyes every half hour.

Other examples:

Doktor mata menasihatkan kami supaya rehatkan mata setiap setengah jam.
= advised us
Doktor mata menasihatkan Ali supaya rehatkan mata setiap setengah jam.
= advised Ali

The rest of the structure (menasihatkan … supaya rehatkan mata setiap setengah jam) stays the same.

Is the register of this sentence formal, informal, or neutral?

The sentence:

Doktor mata menasihatkan saya supaya rehatkan mata setiap setengah jam.

feels neutral to slightly formal:

Uses menasihatkan (more formal than suruh or cakap).
Uses setiap rather than tiap.
No slang or strongly colloquial forms.

It’s suitable for:

Writing (e.g., in a report, essay, or patient notes in plain language).
Polite conversation.

You could make it more formal by using agar, pakar mata, etc., or more informal by using suruh, tiap, cakap, as shown in earlier answers.