Learn Hardcore Indonesian: Saya belum yakin dengan judul skripsi saya.

Saya belum yakin...
= I am not sure yet, but I might be sure later; there is an expectation or possibility that certainty will come in the future.
Saya tidak yakin...
= I am not sure, with no built‑in idea that this might change later. It sounds more definite / more final.

So in this sentence, belum makes it sound softer and less final: you’re still in the process of deciding.

Why is saya used twice: at the beginning and at the end?

The two saya have different grammatical roles:

First Saya = subject (I).
Last saya in judul skripsi saya = possessive (my).

So the structure is:

Saya (I)
belum yakin (am not yet sure)
dengan (about/with)
judul skripsi saya (my thesis title)

Indonesian usually repeats the pronoun to show possession instead of changing its form like English I → my. That’s why you see saya twice.

You could drop the first Saya in casual speech and just say:

Belum yakin dengan judul skripsi saya.

The last saya cannot be dropped if you still want to say my thesis title.

Could I use Aku instead of Saya here? What’s the difference?

Yes, grammatically you can say:

Aku belum yakin dengan judul skripsi aku.

But there are style and politeness differences:

Saya is neutral–polite, used in formal or semi‑formal situations, including with lecturers, in academic writing, and with people you don’t know well.
Aku is informal–intimate, used with close friends, family, or people of similar age in relaxed contexts.

Talking about a skripsi usually involves an academic context (lecturers, supervisors), so Saya is the safer and more natural choice in most real situations.

Why is it judul skripsi and not skripsi judul for “thesis title”?

In Indonesian, the general noun order is:

Head noun + modifying noun

So:

judul = title
skripsi = thesis (undergraduate)

judul skripsi = title (of a) thesis → thesis title

If you say skripsi judul, it sounds like thesis of a title, which is not how Indonesians structure this idea. The same pattern appears in:

buku pelajaran = textbook (book of lessons)
rencana proyek = project plan (plan of a project)

Then you add saya after the whole noun phrase:

judul skripsi saya = my thesis title

Why is dengan used after yakin? Could I use tentang instead?

The verb/adjective yakin (sure, confident) commonly links to its object with certain prepositions:

yakin dengan
yakin akan
yakin terhadap

All of these are used, with slight stylistic preferences.

In this sentence:

Saya belum yakin dengan judul skripsi saya.
= I’m not yet sure about my thesis title.

Using tentang after yakin is much less natural:

✗ Saya belum yakin tentang judul skripsi saya. (sounds odd)

Tentang is common with verbs like berbicara, membahas (talk about, discuss), but not typically with yakin. So stick with dengan / akan / terhadap after yakin, and dengan is very natural in everyday usage.

What exactly does skripsi mean? Is it just “thesis”?

Skripsi is a culture‑specific academic term in Indonesian:

skripsi usually = an undergraduate thesis (for a bachelor’s degree).
tesis = a master’s thesis.
disertasi = a doctoral dissertation.

In English, thesis can refer to different levels depending on context, but in Indonesian, skripsi/tesis/disertasi clearly mark the academic level.

So judul skripsi saya is more precisely my undergraduate thesis title, but in general English it’s natural just to say my thesis title.

Is there any tense here? How do we know if it’s present, past, or future?

Indonesian does not mark tense on the verb the way English does. The sentence:

Saya belum yakin dengan judul skripsi saya.

is neutral and can be understood from context as:

I’m not sure yet (right now).
I wasn’t sure yet (at that time).
I’m still not sure yet (up to now).

The time frame is usually shown by time words or context, for example:

Kemarin saya belum yakin dengan judul skripsi saya.
Yesterday I wasn’t sure yet about my thesis title.
Sampai sekarang saya belum yakin dengan judul skripsi saya.
Until now I’m still not sure about my thesis title.

Belum itself does suggest an ongoing state (not yet), which often feels present‑oriented, but it doesn’t hard‑code a grammatical tense like English does.

Can I drop dengan and just say Saya belum yakin judul skripsi saya?

That sounds unnatural in standard Indonesian.

Yakin normally needs either:

a preposition before a noun phrase:
- yakin dengan / akan / terhadap judul skripsi saya, or
a clause starting with bahwa:
- Saya belum yakin bahwa judul skripsi saya sudah tepat.
  I’m not yet sure that my thesis title is right.

So:

✓ Saya belum yakin dengan judul skripsi saya.
✓ Saya belum yakin bahwa judul skripsi saya tepat.
✗ Saya belum yakin judul skripsi saya. (feels incomplete/incorrect)

What’s the difference between yakin and pasti in this kind of sentence?

Both relate to certainty but are used differently:

yakin = to be sure / confident (a feeling or belief)
pasti = certain, for sure (can be adverb or adjective)

In this structure:

Saya belum yakin dengan judul skripsi saya.
= I’m not yet sure (personally uncertain).

You normally wouldn’t say:

✗ Saya belum pasti dengan judul skripsi saya.

More natural ways to use pasti:

Judul skripsi saya belum pasti.
My thesis title is not final yet / not certain yet.

So to express your own feeling of uncertainty, yakin is the natural choice.

Is this sentence polite/natural to say to a lecturer or supervisor?

Yes, it is appropriate and sounds natural. With a supervisor, you might hear or say:

Saya belum yakin dengan judul skripsi saya.
Saya masih ragu dengan judul skripsi saya.
Saya belum begitu yakin dengan judul skripsi saya.

Using Saya, not Aku, and this kind of structure is standard in a formal or semi‑formal academic context.

Can I say just judul saya instead of judul skripsi saya?

You can, but it’s less clear.

judul saya = my title (could be the title of anything: a book, an article, a video, etc.)
judul skripsi saya = clearly my thesis title.

In an academic context, people might understand judul saya from context, but judul skripsi saya is more precise and typical when talking about a skripsi.

How would I change this sentence if I want to say “We are not sure yet about our thesis title”?

You mainly need to change the subject and the possessive:

If we means you + listener (inclusive): kita
- Kita belum yakin dengan judul skripsi kita.
If we means you + someone else, but not the listener (exclusive): kami
- Kami belum yakin dengan judul skripsi kami.

The structure stays the same; only saya → kita/kami changes.