Learn Hardcore Indonesian: Foto di dinding itu menyimpan banyak kenangan bahagia waktu kecil. - The photo on that wall keeps many happy memories from childhood.

foto di dinding itu is understood as that photo on the wall, not the photo on that wall (though context can sometimes blur this).
Structurally:
- foto = noun
- di dinding = prepositional phrase modifying foto (telling you where it is)
- itu = demonstrative pointing to the noun phrase foto di dinding as a whole

If you really wanted to say the photo on that wall, you would usually say:

foto di dinding itu (and let context disambiguate), or
foto di dinding yang itu if you really need to stress that particular wall (more explicit but also more wordy).

Why is there no word like that or which (a relative pronoun) in foto di dinding itu like we would have in English the photo that is on the wall?

Indonesian often does not require a relative pronoun where English does.

English: the photo that is on the wall
Indonesian: foto di dinding itu

Things to notice:

Indonesian can simply put the prepositional phrase di dinding after the noun to show location.
Adding yang is possible but not necessary:
- foto yang di dinding itu is grammatically possible, but sounds slightly heavier and less natural here, unless you’re contrasting or emphasising it.
In everyday Indonesian, the shortest natural structure is preferred when it’s clear.

So where English uses that/which/who, Indonesian often just uses a phrase after the noun without a linking word.

Why is menyimpan used here for “keeps/holds memories”? Doesn’t menyimpan usually mean “to store/put away” something physical?

Yes, menyimpan literally means to keep / to store / to put something away, often for physical objects:

menyimpan uang di bank = to keep money in the bank
menyimpan buku di rak = to store books on the shelf

But it is very common and natural to use menyimpan figuratively with abstract nouns, including kenangan:

Foto itu menyimpan banyak kenangan.
Tempat ini menyimpan sejarah panjang. = This place holds a long history.

So in this sentence, menyimpan banyak kenangan bahagia is a natural metaphor: the photo “stores” or “holds” many happy memories.

What is the grammatical structure of the sentence Foto di dinding itu menyimpan banyak kenangan bahagia waktu kecil?

The structure is straightforward:

Foto di dinding itu = subject
- foto = noun
- di dinding = prepositional phrase describing the photo
- itu = demonstrative (“that”)
menyimpan = verb (active, transitive)
banyak kenangan bahagia = object
- banyak = quantifier (“many”)
- kenangan = noun (“memories”)
- bahagia = adjective (“happy”)
waktu kecil = time phrase, giving the time related to the memories (“when (I) was little”)

So in English-like order:
That photo on the wall (subject) keeps (verb) many happy childhood memories (object) (from) when (I) was little (time phrase).

Why is kenangan bahagia and not bahagia kenangan, when in English we say happy memories?

In Indonesian, adjectives normally come after the noun:

rumah besar = big house
baju merah = red shirt
kenangan bahagia = happy memories

If you say bahagia kenangan, it sounds wrong or at best very poetic/odd.
The neutral rule: noun + adjective, so kenangan bahagia is the standard order.

How is the plural idea expressed in banyak kenangan bahagia if there is no plural ending like -s?

Indonesian does not usually mark plural with an ending. Plurality is shown by:

Quantifiers like:
- banyak (many)
- beberapa (some)
- dua, tiga, etc. (two, three, etc.)
Context

In banyak kenangan bahagia:

banyak already means many, so kenangan is automatically understood as plural: many memories.

You could also say:

banyak kenangan-kenangan bahagia
but that sounds heavier and usually unnecessary. With banyak, the reduplication is often dropped.

What does waktu kecil literally mean, and why is there no subject like saya?

Literally:

waktu = time / when
kecil = small / little

So waktu kecil literally is when (someone) was little or during childhood.

In full form, you could say:

waktu saya kecil = when I was little
waktu kami kecil = when we were little
waktu dia kecil = when he/she was little

In everyday speech and writing, Indonesian often drops the subject if it’s clear from context.
So waktu kecil by itself is understood as when I was little if the speaker is talking about their own memories.

If you want to be explicit, you can say waktu saya kecil.

Can waktu kecil be replaced with masa kecil? Is there any difference?

Yes, you can say:

banyak kenangan bahagia waktu kecil
banyak kenangan bahagia masa kecil

Differences:

waktu kecil = more informal, very common, sounds like when (I) was little.
masa kecil = slightly more formal/literary, literally childhood period.

Both are natural; waktu kecil is more conversational, masa kecil a bit more “written” or reflective.

Is foto di dinding itu the same as foto di dinding yang itu?

Not exactly.

foto di dinding itu
- default reading: that photo on the wall (highlighting the photo)
- itu is seen as pointing to the whole phrase foto di dinding
foto di dinding yang itu
- more like: the photo on that particular wall or the photo on that one wall (not another)
- here yang itu really singles out the wall (dinding) as that one

In many contexts, foto di dinding itu is enough and more natural.
yang itu is used if you need to contrast or specify more sharply, often when pointing at several options.

Why is there no to be verb, like adalah or adalah yang in this sentence?

Indonesian does not use a to be verb in the same way English does, especially when:

You have a noun + verb + object structure.
Or noun + adjective/noun in simple descriptive sentences.

In Foto di dinding itu menyimpan banyak kenangan bahagia waktu kecil, the main verb is menyimpan, so there is no need (and no place) for a to be verb:

Subject: Foto di dinding itu
Verb: menyimpan
Object: banyak kenangan bahagia
Time phrase: waktu kecil

You would use adalah in patterns like X adalah Y (X is Y), e.g.:

Foto di dinding itu adalah foto keluarga saya.
= That photo on the wall is my family photo.

But here we’re describing what the photo does (it “keeps” memories), not what it is.

What is the role of banyak in menyimpan banyak kenangan bahagia? Could I omit it?

banyak is a quantifier meaning many / a lot of.

menyimpan banyak kenangan bahagia = keeps many happy memories
menyimpan kenangan bahagia = keeps happy memories (no quantity specified)

If you omit banyak, the sentence is still grammatical and natural, just less specific about the number.
Using banyak emphasizes that there are a lot of memories connected to this photo.

Is there any difference between foto and gambar in this context?

Both can refer to visual images, but there is a nuance:

foto = specifically a photograph (taken with a camera/phone).
gambar = a picture more generally; can be a drawing, illustration, painting, or sometimes photo, depending on context.

For a photograph on a wall, foto is the most precise and common word.
If you said:

Gambar di dinding itu menyimpan banyak kenangan bahagia waktu kecil.

it might still be understood, but it could suggest a drawing/painting rather than a photograph.