Learn Hardcore Indonesian: Bukan hanya tetangga laki-laki yang aktif, tetapi juga tetangga perempuan. - Not only male neighbors are active, but also female neighbors.

Use bolded bukan to negate a noun phrase or category. The part after it, bolded hanya tetangga laki-laki, is a noun phrase, so bolded bukan fits well. In contrast, bolded tidak typically negates verbs and adjectives.

Noun phrase: bolded Bukan hanya tetangga laki-laki …
Verb/adjective phrase: bolded Dia tidak hanya bekerja; dia juga belajar. or bolded Mereka tidak hanya rajin, tetapi juga teliti.

That said, bolded tidak hanya … tetapi juga … is widely heard too; see next question for nuance.

Is bolded tidak hanya … tetapi juga … also correct?

Yes. Both bolded bukan hanya … tetapi juga … and bolded tidak hanya … tetapi juga … are common. A handy guideline:

If what follows “not only” is a noun phrase: bolded bukan is more textbook-standard. Example: bolded Bukan hanya guru, tetapi juga siswa yang hadir.
If what follows is a verb/adjective: bolded tidak feels more natural. Example: bolded Dia tidak hanya pintar, tetapi juga rajin.

Your sentence has a noun phrase, so bolded bukan is the cleanest choice, but bolded tidak is not unusual in real usage.

What does bolded yang do in bolded tetangga laki-laki yang aktif?

Bolded yang turns what follows into a relative clause, “who/that …”. So bolded tetangga laki-laki yang aktif = “the male neighbor(s) who are active.” It specifically picks out the male neighbors that have the property “active.”

Can I drop bolded yang and say bolded tetangga laki-laki aktif?

Grammatically possible, and it reads “active male neighbors.” However, with bolded bukan hanya … tetapi juga … the bolded yang version makes the contrastive focus on “active” clearer. Without bolded yang it sounds more like a plain stacked description rather than “the ones who are active.”

Does bolded yang aktif apply to both groups or only the first one?

Semantically it applies to both. The second half omits it by parallelism. You could make it explicit:

bolded Bukan hanya tetangga laki-laki yang aktif, tetapi juga tetangga perempuan yang aktif. (correct but wordy) A smoother symmetric option:
bolded Yang aktif bukan hanya tetangga laki-laki, tetapi juga tetangga perempuan.

Do I need the comma before bolded tetapi?

It’s common and acceptable to place a comma before bolded tetapi in contrasts. In short clauses it’s sometimes omitted, but keeping it is safe. For a stronger pause, a semicolon or period also works:

bolded … yang aktif; tetapi juga …
bolded … yang aktif. Tetapi juga …

What’s the difference between bolded tetapi, bolded tapi, and bolded melainkan?

bolded tetapi = “but,” formal/neutral.
bolded tapi = “but,” informal.
bolded melainkan = “but rather,” used after a negation to replace/correct. It fits especially well in the pattern:
- bolded Bukan hanya X, melainkan juga Y. (more formal than bolded tetapi juga)

Is bolded tetangga singular or plural here?

It’s number-neutral; context decides. To force singular or plural:

Singular: bolded seorang tetangga laki-laki …; bolded tetangga laki-laki itu …
Plural: bolded para tetangga …; bolded tetangga-tetangga …; bolded beberapa tetangga …

Are bolded laki-laki and bolded perempuan the best words here? What about bolded pria/wanita or bolded cowok/cewek?

All are possible, but they differ in register:

Neutral/common: bolded laki-laki, perempuan.
Formal/news: bolded pria, wanita.
Informal/slangy: bolded cowok, cewek. There’s also bolded lelaki (a single-word synonym of bolded laki-laki). Some speakers prefer bolded perempuan over bolded wanita in formal writing for sociolinguistic reasons, but both are widely used.

Why is bolded laki-laki written with a hyphen?

It’s a reduplicated form (bolded laki + laki) that conventionally means “male,” and such reduplication is written with a hyphen in Indonesian orthography. A single-word alternative is bolded lelaki.

Why bolded tetangga laki-laki and not bolded laki-laki tetangga?

In Indonesian, the head noun usually comes first, followed by modifiers: noun + descriptor. So:

bolded tetangga laki-laki (male neighbor)
bolded rumah besar (big house)
bolded guru baru (new teacher)

Can I move bolded juga to the second phrase only, like bolded …; tetangga perempuan juga?

Yes. These are all natural:

bolded Bukan hanya tetangga laki-laki yang aktif, tetapi juga tetangga perempuan. (your version)
bolded Bukan hanya tetangga laki-laki yang aktif; tetangga perempuan juga. (juga after the second NP)
bolded Bukan hanya tetangga laki-laki; tetangga perempuan juga aktif. (repeats the predicate for clarity)

Is there a more symmetric way to say it?

Yes, front the focused predicate:

bolded Yang aktif bukan hanya tetangga laki-laki, tetapi juga tetangga perempuan. This makes it very clear that “active” is the shared property.

Is bolded aktif the right word? How does it differ from bolded rajin or bolded giat?

bolded aktif = active/involved (e.g., in activities, organizations): bolded aktif di kegiatan RT.
bolded rajin = diligent/industrious (habitual effort): bolded rajin bekerja.
bolded giat = active/energetic (often formal/literary): bolded giat mengikuti program. Use bolded aktif when you mean “engaged/involved,” which fits this community context.

How do I make it clearly singular?

Add a determiner or classifier:

bolded Bukan hanya tetangga laki-laki itu yang aktif, tetapi juga tetangga perempuan itu. (that specific male/female neighbor)
bolded Bukan hanya seorang tetangga laki-laki yang aktif, tetapi juga seorang tetangga perempuan. (one male neighbor … one female neighbor)

Is there a “both … and …” version without the negation?

Yes:

bolded Baik tetangga laki-laki maupun tetangga perempuan aktif.
bolded Tetangga laki-laki dan tetangga perempuan sama-sama aktif. These assert inclusion without the “not only” framing.