Setelah proposal skripsi saya disetujui oleh dosen pembimbing, baru saya mulai menulis skripsi.

Setelah means after and introduces a time clause.

So:

• Setelah proposal skripsi saya disetujui oleh dosen pembimbing = After my thesis proposal was approved by my supervisor
• baru saya mulai menulis skripsi = only then did I start writing my thesis

Yes, the order can be reversed. For example:

• Saya baru mulai menulis skripsi setelah proposal skripsi saya disetujui oleh dosen pembimbing.

That version is also natural. The original sentence puts the after-clause first to set the time/background before the main point.

No. In this sentence, baru does not mean new.

Here, baru means something like:

• only then
• not until then
• only after that

So:

• baru saya mulai menulis skripsi = only then did I start writing my thesis

This is a very common Indonesian use of baru. It often marks that something happened only after a certain condition was met.

Compare:

• Saya baru makan = I just ate / I only ate recently
• Setelah selesai kerja, baru saya pulang = Only after finishing work did I go home

So in your sentence, baru highlights that the writing did not begin before the proposal approval.

Both are possible, but they are not exactly the same in emphasis.

• baru saya mulai menulis skripsi strongly emphasizes only then
• saya baru mulai menulis skripsi is also natural, but sounds a bit more neutral

Placing baru before the subject can give the sentence a slightly more formal or emphatic feel, especially after a fronted time clause like setelah ....

So the original structure is highlighting sequence:

1. proposal approved
2. only then I started writing

Skripsi is a specific Indonesian academic term. It usually refers to an undergraduate final thesis or undergraduate research paper.

Roughly:

• skripsi = undergraduate thesis
• tesis = master's thesis
• disertasi = doctoral dissertation

In English, people often translate skripsi simply as thesis, but the exact academic level is specifically undergraduate in Indonesian usage.

So:

• proposal skripsi = thesis proposal / undergraduate thesis proposal
• menulis skripsi = write the thesis

Because the two instances of saya have different roles:

1. proposal skripsi saya
   Here saya means my. It shows possession: my thesis proposal.

2. baru saya mulai menulis skripsi
   Here saya is the subject: I.

Indonesian uses the same word saya for both I and my, depending on position.

So:

• after a noun: possession
  buku saya = my book
• as a subject:
  saya menulis = I write

Disetujui is a passive verb.

It comes from:

• setuju = agree
• menyetujui = to approve / to agree to something
• disetujui = to be approved

So:

• Dosen pembimbing menyetujui proposal skripsi saya = The supervisor approved my thesis proposal
• Proposal skripsi saya disetujui (oleh dosen pembimbing) = My thesis proposal was approved (by the supervisor)

The prefix di- is a common marker of the passive in Indonesian.

Oleh means by and introduces the agent in a passive sentence.

So:

• proposal skripsi saya disetujui oleh dosen pembimbing = my thesis proposal was approved by my supervisor

In many Indonesian passive sentences, oleh is optional, especially when the agent is obvious or not important.

So these are both possible:

• Proposal skripsi saya disetujui oleh dosen pembimbing
• Proposal skripsi saya disetujui dosen pembimbing

The version with oleh is a bit clearer and sometimes a little more formal.

Dosen means lecturer or university instructor.
Pembimbing means advisor, supervisor, or mentor.

Together, dosen pembimbing means the academic supervisor who guides the student, especially for a thesis or final project.

Depending on context, it may be translated as:

• supervisor
• thesis advisor
• academic advisor

In this sentence, supervisor or thesis advisor is the most natural translation.

The passive puts the focus on the proposal, not on the supervisor.

Compare:

• Dosen pembimbing menyetujui proposal skripsi saya, lalu saya mulai menulis skripsi.
  = The supervisor approved my proposal, then I started writing.

• Setelah proposal skripsi saya disetujui oleh dosen pembimbing, baru saya mulai menulis skripsi.
  = After my proposal was approved by my supervisor, only then did I start writing.

The passive is very natural here because the important thing is the approval status of the proposal, not the person doing the approving.

Indonesian often uses passive in formal or academic contexts.

Because they refer to two related but different things:

• proposal skripsi = the proposal for the thesis
• skripsi = the actual thesis

So the sequence is:

1. first, the thesis proposal is approved
2. then, the student starts writing the thesis itself

Repeating skripsi is normal and clear here. It helps show that the proposal and the final work are connected.

In practice, it is understood as my thesis proposal.

Indonesian noun phrases often stack nouns together:

• proposal skripsi = thesis proposal
• judul skripsi = thesis title
• topik skripsi = thesis topic

Then saya at the end marks possession of the whole phrase:

• proposal skripsi saya = my thesis proposal

So you should understand the structure as:

• [proposal skripsi] saya not
• proposal [skripsi saya]

Although context matters, in this sentence the intended meaning is very clearly my thesis proposal.

The comma separates the introductory subordinate clause from the main clause.

• Setelah proposal skripsi saya disetujui oleh dosen pembimbing, = time/background clause
• baru saya mulai menulis skripsi. = main clause

This is similar to English:

• After my thesis proposal was approved by my supervisor, I started writing my thesis.

In Indonesian, the comma is commonly used when a long clause comes before the main clause.

Yes, it sounds fairly formal and natural, especially in academic or written Indonesian.

Reasons it sounds formal:

• use of the passive: disetujui
• explicit agent phrase: oleh dosen pembimbing
• emphatic sequencing with baru
• academic vocabulary: proposal skripsi, dosen pembimbing

In casual speech, someone might say a simpler version, such as:

• Setelah proposal saya disetujui dosen pembimbing, saya baru mulai nulis skripsi.

That is less formal because:

• nulis is the casual form of menulis
• the structure is slightly less careful

Yes. That is a very good natural English translation.

It captures the function of baru well, because only started ... after expresses the same idea of delayed action.

Some natural English versions are:

• I only started writing my thesis after my supervisor approved my thesis proposal.
• Only after my thesis proposal was approved by my supervisor did I start writing my thesis.
• After my thesis proposal was approved by my supervisor, only then did I start writing my thesis.

The second and third are closer to the Indonesian structure, while the first sounds more natural in everyday English.