Sebelum tidur, saya mengisi daya ponsel di kamar.

Sebelum means before, and tidur means sleep / to sleep. Together, sebelum tidur means before sleeping or before going to bed.

Putting this time phrase at the beginning sets the time context first, just like English Before bed, .... Indonesian often puts time expressions at the start of a sentence, but it is also possible to place them later:

Sebelum tidur, saya mengisi daya ponsel di kamar.
Saya mengisi daya ponsel di kamar sebelum tidur.

Both are natural.

In Indonesian, the subject is often omitted in time expressions when it is obvious from context.

So sebelum tidur literally looks like before sleeping, with no subject stated. Since the main clause has saya, it is naturally understood that I am the one sleeping.

You could say sebelum saya tidur, and that is grammatically correct, but it sounds a bit more explicit. In everyday speech, sebelum tidur is very common and natural.

It is basically a verb here: to sleep.

After words like sebelum and sesudah, Indonesian often uses a verb directly without needing a separate word like English before going to sleep. So sebelum tidur is literally before sleep/to sleep, but naturally understood as before sleeping.

Mengisi daya means to charge something, especially an electronic device.

It is made up of:

• mengisi = to fill
• daya = power / energy

So the literal idea is to fill with power, which becomes to charge in natural English.

This is a standard and fairly formal way to say charge. In casual speech, many people also say mengecas or ngecas.

Examples:

• Saya mengisi daya ponsel. = I charge my phone.
• Saya mengecas ponsel. = I charge my phone.
  This is more colloquial.

Because mengisi by itself usually means to fill something, and without daya the meaning is unclear.

For example:

• mengisi botol = fill a bottle
• mengisi formulir = fill out a form

If you say mengisi ponsel, it sounds incomplete or unnatural, because a phone is not the thing you normally fill directly. By adding daya, you specify that you are filling it with power, meaning charging it.

Isi is the root word. Mengisi is the active verb form.

This is a very common pattern in Indonesian:

• root: isi
• active verb: mengisi = to fill

Because ponsel is the object of the verb, Indonesian normally uses the meN- active form here:

• Saya mengisi daya ponsel.

Using just isi would not fit standard sentence grammar in this context.

Both saya and aku mean I, but they differ in tone.

• saya = neutral, polite, standard
• aku = more informal, personal, casual

So:

• Sebelum tidur, saya mengisi daya ponsel di kamar. sounds neutral and standard.
• Sebelum tidur, aku mengisi daya ponsel di kamar. is also correct, but more casual.

A textbook sentence often uses saya because it is safe in most situations.

Ponsel means mobile phone / cell phone. It is a standard Indonesian word.

Other common possibilities are:

• telepon genggam = mobile phone, more formal/longer
• HP = very common in everyday speech, from handphone
• smartphone = also used, especially for smartphones

So ponsel is correct and natural, especially in standard Indonesian.

Di kamar literally means in the room.

However, kamar very often refers specifically to a bedroom in everyday Indonesian, especially if no other context is given. So in many situations, di kamar would naturally be understood as in the bedroom.

Context decides the best translation.

Because here di is a preposition meaning in / at / on, and prepositions are written separately from the following word.

So:

• di kamar = in the room
• di rumah = at home

This is different from the prefix di-, which marks the passive verb and is attached to the verb:

• diisi = is filled / is charged
• dibuka = is opened

This difference is very important in Indonesian spelling.

The main clause is:

saya = subject
mengisi daya = verb
ponsel = object
di kamar = place

So the core pattern is:

Subject + Verb + Object + Place

The full sentence adds a time phrase at the beginning:

Sebelum tidur, + saya mengisi daya ponsel di kamar.

That is a very common Indonesian sentence structure.

Yes, it can.

For example:

• Sebelum tidur, saya mengisi daya ponsel di kamar.
• Sebelum tidur, di kamar saya mengisi daya ponsel.

But the first version is more natural and straightforward for most contexts.

Indonesian allows some flexibility with adverbial phrases like place and time, but the most common order here is still: Subject + Verb + Object + Place

Indonesian does not normally use articles like a, an, or the.

So:

• ponsel can mean a phone, the phone, or just phone
• kamar can mean a room, the room, or bedroom, depending on context

The listener figures out the exact meaning from the situation.

That is why ponsel and kamar appear without articles.

Yes.

For example:

• Sebelum tidur, saya mengisi daya HP di kamar.
• Sebelum tidur, saya mengisi baterai ponsel di kamar.

These are slightly different in focus:

• mengisi daya ponsel = charge the phone
• mengisi baterai ponsel = charge the phone’s battery

Both are understandable. The original sentence is natural and standard.

It is neutral to standard Indonesian.

Reasons:

• saya is polite/neutral
• mengisi daya is standard wording
• ponsel is standard vocabulary

A more casual version might be: Sebelum tidur, aku ngecas HP di kamar.

That means the same thing, but the register is much more informal.

Yes, depending on context.

Literally, tidur is sleep, so sebelum tidur can cover:

• before going to sleep
• before falling asleep
• before bed

In everyday translation, before going to bed is often the most natural English version, but the Indonesian phrase itself is a little broader.