Learn Hardcore Indonesian: Saya merasa frustrasi ketika menunda-nunda tugas sampai detik terakhir. - I feel frustrated when I procrastinate tasks until the last second.

Saya – polite/neutral, safe in almost any situation (talking to strangers, in class, at work, in writing).
Aku – more informal, used with friends, family, people of similar age/status.
Gue / Gua – very informal, mainly in Jakarta slang and casual speech.

In this sentence, Saya makes the sentence sound polite and a bit more formal or “book-like,” which is natural in learning materials or written Indonesian.

What does merasa add? Could I just say Saya frustrasi ketika…?

Merasa literally means “to feel”.

Saya merasa frustrasi… = “I feel frustrated…”
Saya frustrasi… is also understandable and sometimes used in speech, but it sounds slightly less natural or less complete, especially in more formal or standard Indonesian.

Using merasa:

makes it clear we’re talking about an inner feeling, not describing a permanent trait.
fits very well with adjectives of emotion:
- merasa sedih – feel sad
- merasa senang – feel happy
- merasa marah – feel angry

So Saya merasa frustrasi… is the most natural standard way to say “I feel frustrated…”

Is frustrasi a natural Indonesian word, or is it just an English loan?

Frustrasi is a loanword (from European languages) but it is very common and natural in Indonesian.

Some related or alternative words:

frustrasi – frustration (noun) / frustrated (adjective, in context)
frustrasi sekali – very frustrated
bikin frustrasi – (it) makes (someone) frustrated
kesal, sebel – annoyed/irritated (more colloquial, a bit different nuance)

In Saya merasa frustrasi, frustrasi works like an adjective: “I feel frustrated.” It’s perfectly normal Indonesian.

What does the reduplication in menunda-nunda mean compared to just menunda?

Both come from the base verb tunda (to delay).

menunda – to delay / to postpone (once, in a neutral way)
- Saya menunda tugas itu sampai besok.
  “I postponed that assignment until tomorrow.”
menunda-nunda – to keep delaying, repeatedly putting something off, “to procrastinate”
- Dia menunda-nunda tugasnya.
  “He keeps putting off his assignment.”

The reduplication (tunda → tunda-nunda) suggests:

repetition / habit
dragging something out
often a negative nuance (procrastination, not just a neutral rescheduling)

So in this sentence menunda-nunda is well translated as “to procrastinate.”

What exactly does tugas mean here? Is it homework, a task, or a job?

Tugas is a general word for “task,” “assignment,” or “duty.”

What it refers to depends on context:

school or university → assignment / homework
work / job → work task / duty
general → task / responsibility

In this sentence, without more context, tugas can naturally be understood as assignments or tasks in general (school, work, or any responsibilities).

What is the function of ketika here, and can I replace it with saat or waktu?

Ketika is a conjunction meaning “when” (for a time clause).

Saya merasa frustrasi ketika menunda-nunda tugas…
“I feel frustrated when I procrastinate on tasks…”

You can usually replace ketika with:

saat – also “when / at the time when,” very common in spoken and written Indonesian.
waktu – literally “time,” but often used in the sense “when” in everyday speech.

In this particular sentence:

Saya merasa frustrasi ketika menunda-nunda tugas…
Saya merasa frustrasi saat menunda-nunda tugas…
Saya merasa frustrasi waktu menunda-nunda tugas… (more informal)

All are acceptable. Ketika and saat sound more neutral/standard; waktu is more colloquial as a conjunction.

What does sampai detik terakhir literally mean, and is it an idiom?

Literally:

sampai – until / up to
detik – second (unit of time)
terakhir – last

So sampai detik terakhir literally means “until the last second.”

It is used very similarly to English:

can be literal (until the final second of a countdown)
often just means “until the very last moment,” implying you left no buffer time and did it at the latest possible point.

Yes, it’s also an idiomatic-sounding phrase, but its literal meaning is clear and matches English very closely.

Could I move the ketika clause to the front, like in English: “When I procrastinate…, I feel frustrated”?

Yes. Indonesian allows both orders, just like English:

Saya merasa frustrasi ketika menunda-nunda tugas sampai detik terakhir.
Ketika menunda-nunda tugas sampai detik terakhir, saya merasa frustrasi.

Both are grammatically correct and natural.

Putting Ketika… at the beginning:

slightly emphasizes the condition/situation first (“When I procrastinate…”),
is quite common in written or more formal styles.

The meaning does not change; it’s just a stylistic choice.

Why doesn’t the sentence specify past, present, or future? How do I know the tense?

Indonesian does not mark tense with verb changes like English. The verb form stays the same; context and time words do the work.

Saya merasa frustrasi ketika menunda-nunda tugas sampai detik terakhir.
Can mean:

“I feel frustrated when I procrastinate (in general).” – general/habit
“I felt frustrated when I procrastinated (that time).” – past
“I will feel frustrated when I procrastinate (later).” – future (less common without more context)

To make it clearer, you add time markers:

Dulu saya merasa frustrasi… – I used to feel frustrated… (past)
Sekarang saya merasa frustrasi… – Now I feel frustrated… (present)
Nanti saya akan merasa frustrasi… – Later I will feel frustrated… (future)
Saya sering merasa frustrasi ketika… – I often feel frustrated when… (habit)

So the base sentence is time-neutral; context decides.

Why is there no subject after ketika? Shouldn’t it be ketika saya menunda-nunda tugas?

You can say ketika saya menunda-nunda tugas, and it is correct.

But Indonesian often omits the subject in the second clause when:

it is the same subject as the main clause, and
the meaning is still clear.

Here:

Main clause: Saya merasa frustrasi (subject = Saya)
Time clause: (Saya) menunda-nunda tugas… – the subject is understood to be the same Saya.

So both are natural:

Saya merasa frustrasi ketika menunda-nunda tugas…
Saya merasa frustrasi ketika saya menunda-nunda tugas…

The first is just more concise, and very typical.

Is this sentence formal, informal, or neutral in tone?

It is neutral to slightly formal, mainly because of:

Saya – neutral–polite pronoun
the complete structure with merasa and ketika – more standard/”textbook” style

It would be fine in:

school essays
conversations with teachers
written explanations
semi-formal speech

To make it more casual with friends, someone might say:

Aku frustrasi kalau suka nunda-nunda tugas sampai detik terakhir.
(more colloquial word choices and structure)

Are there more everyday, colloquial alternatives to merasa frustrasi?

Yes. Depending on the nuance you want:

Aku kesal kalau menunda-nunda tugas… – I get annoyed when I procrastinate…
Aku sebel banget kalau nunda-nunda tugas… – I get really fed up when I procrastinate… (very informal)
Aku stres kalau nunda-nunda tugas… – I get stressed when I procrastinate…

Merasa frustrasi sounds a bit more formal or “psychological” in tone, while kesal, sebel, and stres sound more like everyday spoken Indonesian.