Learn Hardcore Indonesian: Saya sama sekali tidak cemas; apalagi teman perempuan saya selalu tenang. - I am not worried at all; moreover my female friend is always calm.

Before the negation: Saya sama sekali tidak cemas.
After the predicate: Saya tidak cemas sama sekali. With noun predicates, use bukan: Saya sama sekali bukan dokter. Avoid the ungrammatical order tidak sama sekali cemas.

Why is it tidak cemas and not bukan cemas?

tidak negates verbs, adjectives, and adverbs: tidak cemas, tidak suka, tidak cepat.
bukan negates noun phrases or pronouns used as predicates: Dia bukan dokter, Itu bukan ide saya. Since cemas is an adjective/stative verb, use tidak.

Is cemas the right word for “anxious/worried”? How does it differ from similar words?

cemas: anxious/uneasy (internal unease).
khawatir: worried/concerned (often about a specific outcome).
gelisah: restless, fidgety.
gugup: nervous (performance/spotlight jitters).
tegang: tense.
panik: panicked.
deg-degan: colloquial, “heart pounding,” nervous-excited. In your sentence, cemas and khawatir are both fine; cemas leans slightly more to anxious unease.

How is apalagi functioning here?

Here apalagi is additive: “what’s more,” “all the more so,” “especially since.” So:

Saya sama sekali tidak cemas; apalagi teman perempuan saya selalu tenang. ≈ “I’m not anxious at all; what’s more, my (female) friend is always calm,” implying her calmness is a reinforcing reason. Note: apalagi also has a “let alone” use after a negative (see below), so context matters.

Could I use another connector instead of apalagi?

Yes, to avoid ambiguity:

lagipula: Saya sama sekali tidak cemas; lagipula, teman perempuan saya selalu tenang.
terlebih lagi / selain itu: slightly more formal.
apalagi karena …: “especially since …” (clear reason) — …; apalagi karena teman perempuan saya selalu tenang.

Is the semicolon necessary? Could I use a comma?

A comma is very common: …, apalagi …. The semicolon is acceptable to mark a stronger break. Both are fine in modern Indonesian.

Does teman perempuan mean “girlfriend”?

Literally it means “female friend,” and that’s the default interpretation. It can be ambiguous in speech. If you mean “girlfriend,” use:

pacar (most common, gender-neutral): pacar saya
kekasih (formal/literary) Colloquial options exist (cewek, doi), but pacar is the safe, standard choice.

Other ways to say “my female friend” or “my girlfriend”? Any difference in nuance?

Female friend:
- teman perempuan saya (neutral)
- teman saya perempuan (focus on “my friend (is) female”)
- teman perempuanku (informal; possessive suffix -ku)
- Colloquial: teman cewek saya/temen cewekku
Girlfriend:
- pacar saya/pacarku
- More formal: kekasih saya Note: teman wanita is used but can sound stiff/dated; prefer perempuan in everyday speech.

Formality and tone: perempuan, wanita, cewek — which should I use?

perempuan: neutral, common in everyday and formal contexts; safe default.
wanita: formal/polite register (organizations, signage), but in compounds teman wanita may feel stiff.
cewek: slang/informal (“girl”). For clarity and neutrality, choose perempuan.

Why is selalu placed before tenang? Can it move?

Adverbs of frequency typically precede the predicate:

teman perempuan saya selalu tenang (natural) Fronting for emphasis is possible but marked: Selalu tenang teman perempuan saya (poetic/headline-like). Don’t put selalu at the very end.

Is Saya tidak cemas sama sekali also correct?

Yes. Both are idiomatic:

Saya sama sekali tidak cemas.
Saya tidak cemas sama sekali. Choose whichever flows better for you.

How would a casual version sound?

Aku sama sekali nggak cemas; lagipula pacarku selalu tenang.
Even more colloquial: Aku nggak cemas sama sekali; apalagi temen cewekku tuh kalem banget.

Could apalagi here be misread as “let alone”? How do I avoid that?

Yes. The pattern “X tidak …, apalagi Y …” is often read as “X is not …, let alone Y … (even less Y).” Because your second clause is positive, some readers may stumble. To be crystal clear, prefer:

…, lagipula …
…, terlebih lagi …
…, apalagi karena teman perempuan saya selalu tenang.

What related forms of cemas should I know?

Noun: kecemasan (anxiety) — kecemasan yang berlebihan
Causative/descriptor: mencemaskan (to worry; worrisome) — Beritanya mencemaskan.
Synonymous descriptor: mengkhawatirkan — Situasinya mengkhawatirkan. All pair naturally with saya/aku as object when needed: Itu mencemaskan saya.