Saya ingin menutup tahun ini dengan tenang pada Desember sambil menulis di buku harian.

Yes. Both ingin and mau can mean want, but they feel a little different.

• Saya ingin ... = I want to ... in a slightly more neutral, thoughtful, or polite way
• Saya mau ... = also I want to ..., but often feels more direct or conversational

In this sentence, ingin fits well because the tone is reflective and calm.

So these are both possible:

• Saya ingin menutup tahun ini ...
• Saya mau menutup tahun ini ...

But ingin sounds a bit more natural for this kind of personal statement.

Yes, literally menutup tahun ini means to close this year.

Breakdown:

• menutup = to close
• tahun ini = this year

In natural English, the idea is something like:

• to end this year
• to wrap up this year
• to finish this year

Indonesian often uses menutup metaphorically this way, just like English can say close out the year.

Because menutup is the verb form meaning to close.

• tutup can be a root word and can also function as an imperative or adjective-like word depending on context
• menutup is the active verb with the meN- prefix

Examples:

• Tutup pintu! = Close the door!
• Saya menutup pintu. = I close / am closing the door.

So in your sentence, since Saya is doing the action, menutup is the correct form.

Tahun ini means this year.

In Indonesian, demonstratives like ini and itu usually come after the noun.

So:

• tahun ini = this year
• buku ini = this book
• rumah itu = that house

This is different from English, where this usually comes before the noun.

Dengan tenang means calmly or in a calm way.

Breakdown:

• dengan = with
• tenang = calm

Together, dengan tenang works like an adverbial phrase describing how the speaker wants to end the year.

So:

• menutup tahun ini dengan tenang = to end this year calmly

You may sometimes see just tenang in other sentence types, but dengan tenang is a very common and natural way to express calmly.

Yes, many speakers would also say di Desember, and in everyday conversation that is very common.

However, there is a small nuance:

• pada Desember sounds a bit more formal or careful
• di Desember sounds more casual and conversational

Since Desember is a time expression, pada is often taught as a good choice for in/on/at with times.

So these are both possible:

• pada Desember
• di Desember

If you want a more standard or slightly formal version, pada Desember is a good choice.

Here it means in December.

When Indonesian uses pada with a month like Desember, English normally translates it as in:

• pada Desember = in December

English uses different prepositions depending on the type of time expression:

• in December
• on Monday
• at night

Indonesian does not match English prepositions one-for-one, so it is better to learn the Indonesian expression as a whole.

Sambil means while, while also, or at the same time as.

In your sentence:

• sambil menulis di buku harian = while writing in a diary / journal

It connects two actions happening together:

1. menutup tahun ini dengan tenang pada Desember
2. menulis di buku harian

So the speaker wants to end the year calmly, while also writing in a journal.

Because in Indonesian, if the subject is already clear, it is often omitted in the second part of the sentence.

Here, Saya at the beginning already tells us who is doing the actions. So sambil menulis naturally means:

• while I write
• while writing

You could say sambil saya menulis, but it is less smooth here and usually unnecessary unless you want extra emphasis or clarity.

It means in a diary or more naturally in my journal/diary.

Breakdown:

• di = in / on / at, depending on context
• buku harian = diary, journal

With something you write inside, English normally says in:

• menulis di buku harian = to write in a diary/journal

Even though di can have several meanings, here in is the natural English translation.

Yes. Indonesian often leaves possession unstated when it is obvious from context.

So menulis di buku harian can naturally be understood as:

• writing in a diary
• writing in my diary

If you want to make the possession explicit, you could say:

• menulis di buku harian saya = writing in my diary

Without saya, it still sounds perfectly natural.

Yes, the word order is natural. Indonesian is fairly flexible, especially with time expressions and adverbial phrases.

Original:

• Saya ingin menutup tahun ini dengan tenang pada Desember sambil menulis di buku harian.

Possible variations:

• Saya ingin menutup tahun ini pada Desember dengan tenang sambil menulis di buku harian.
• Pada Desember, saya ingin menutup tahun ini dengan tenang sambil menulis di buku harian.

These all work, though the original has a smooth, reflective flow.

Buku harian is a very common and clear way to say diary.

• buku = book
• harian = daily

So literally it is something like daily book.

Jurnal also exists, but it can mean journal, and depending on context it may sound more formal, academic, or modern. For a personal diary, buku harian is very standard and easy to understand.

Yes, definitely. It sounds reflective, personal, and slightly literary.

Reasons:

• Saya ingin gives a thoughtful tone
• menutup tahun ini is metaphorical
• dengan tenang adds an emotional mood
• sambil menulis di buku harian makes it feel introspective

So this does not sound like a basic factual sentence only; it sounds like someone expressing a personal end-of-year feeling or intention.