Learn Hardcore Indonesian: Kami menaruh uang di dalam kotak donasi di depan panggung. - We put money in the donation box in front of the stage.

the speaker is saying that their group (not including the listener) put the money in the donation box. If the speaker wanted to include the listener as part of the group that put in the money, they would say:

Kita menaruh uang di dalam kotak donasi …

What does menaruh mean exactly, and is it different from meletakkan or memasukkan?

The base word of menaruh is taruh, which means to put / place (something somewhere).

menaruh = to put/place something somewhere
meletakkan (from letak) is very close in meaning, often interchangeable with menaruh, especially in standard/written Indonesian.
memasukkan (from masuk = to enter) = to put something into (focus on moving something inside an enclosed space)

In this sentence:

Kami menaruh uang di dalam kotak donasi …

the idea is we put/placed the money in the donation box. You could also say:

Kami memasukkan uang ke dalam kotak donasi …
(more literally: We put the money into the donation box, emphasizing the movement into the box)

Both are acceptable, but memasukkan … ke dalam stresses movement, while menaruh … di dalam stresses the final location.

Why is it di dalam kotak and not just di kotak? What is the difference between di and di dalam?

di = at / in / on (a general location)
di dalam = inside (specifically emphasizing the interior)

di dalam kotak literally means inside the box, while di kotak is more like at the box / at the box area, and can feel a bit vague.

In many contexts, di kotak donasi would still be understood as “in the donation box,” but di dalam kotak donasi is clearer that the money is inside it, not just placed near or on it.

So:

Kami menaruh uang di dalam kotak donasi …
= We put the money inside the donation box.

Why is it di dalam and not ke dalam? What is the difference?

This is a common point of confusion:

di = indicates location (where something is)
ke = indicates direction (movement towards a place)
di dalam = inside (as a location)
ke dalam = into (movement into the inside)

So:

menaruh uang di dalam kotak
= to put money (so that it ends up) inside the box (focus on final location)

If you use memasukkan, you normally pair it with ke dalam:

memasukkan uang ke dalam kotak
= put money into the box (focus on movement into)

In your sentence, menaruh … di dalam is grammatically fine because you’re describing the final place where the money is.

What exactly does kotak donasi mean? Is donasi an Indonesian word or a loan word?

kotak = box
donasi = donation (a loan word from English donation, via Dutch/English influence)

In Indonesian, it is very common to form “Noun + Noun” structures:

kotak donasi = donation box
kotak surat = mailbox
kotak makan = lunch box / food container

donasi is widely used and considered normal, especially in modern, urban, or formal contexts.

There is also a native word sumbangan (donation, contribution):

kotak sumbangan = donation box

Both kotak donasi and kotak sumbangan are correct; kotak donasi sounds slightly more modern/neutral, kotak sumbangan feels a bit more traditional/Indonesian-native in flavor.

What does di depan panggung mean literally, and why not just di panggung?

panggung = stage (for performance)
depan = front
di depan panggung = in front of the stage (in the area facing the stage)

If you said:

di panggung = on the stage

So:

Kotak donasi di depan panggung
= The donation box is in front of the stage (on the ground, where the audience is)
Kotak donasi di panggung
= The donation box is on the stage (on the platform, with the performers)

The original sentence wants to say the box is in front of the stage, so di depan panggung is the correct choice.

Can di depan also mean “before” in a time sense, like “before the show”?

di depan is almost always spatial: in front of, ahead of.

For time, Indonesian normally uses:

sebelum = before
sesudah / setelah = after

So:

sebelum pertunjukan = before the show
di depan panggung = in front of the stage (physical location)

You generally would not use di depan to mean “before” in time expressions.

Is uang countable? Do I need a word like “some” or “the” in Indonesian?

uang means money in general and is uncountable, similar to English.

Indonesian does not use articles like a, an, or the.
Context usually tells you whether it means some money, the money, etc.

In this sentence:

Kami menaruh uang di dalam kotak donasi …

it naturally means we put (some) money in the donation box.

If you want to be more specific, you can add:

sejumlah uang = a certain amount of money
sedikit uang = a little money
banyak uang = a lot of money
uang itu = that money / the money

Example:

Kami menaruh sejumlah uang di dalam kotak donasi.
= We put a certain amount of money in the donation box.

Is the word order di dalam kotak donasi di depan panggung fixed, or can I move the phrases around?

The normal, most natural order is:

di dalam kotak donasi di depan panggung

This goes from smaller location → larger context:
inside the box → which box? the donation box → where is that box? in front of the stage.

In Indonesian, you could move things a bit, but some reorders sound odd or change the focus. For example:

di depan panggung di dalam kotak donasi
sounds unnatural, as if “in front of the stage” is being used to modify “inside the donation box” in a confusing way.

It’s best to keep it as:

di dalam kotak donasi di depan panggung

or, if you need to emphasize the box’s location, you could split into two sentences:

Kami menaruh uang di dalam kotak donasi. Kotak itu ada di depan panggung.
= We put the money in the donation box. The box is in front of the stage.

How formal or informal is this sentence? Would it be okay in spoken Indonesian?

The sentence:

Kami menaruh uang di dalam kotak donasi di depan panggung.

is neutral and natural. It’s fine in:

everyday spoken Indonesian
written Indonesian (stories, reports, etc.)

If you wanted to sound a bit more formal or explicit, you might see:

Kami memasukkan uang ke dalam kotak donasi yang berada di depan panggung.

But for normal conversation and most writing, the original sentence is perfectly appropriate.