Film itu jelek.

In Indonesian, the verb to be is often left out in simple present-tense sentences.

So:

• Film itu jelek = That film is bad / The film is bad

There is no need to add a word for is here.

This is very normal in Indonesian, especially when the predicate is:

• an adjective: Dia tinggi = He is tall
• a noun: Saya guru = I am a teacher
• sometimes a location phrase: Buku itu di meja = The book is on the table

Itu usually means that, but in many contexts it can also work a bit like the in English.

So film itu can mean:

• that film
• the film

Which one sounds best depends on context.

In this sentence, itu points to a specific film that both speaker and listener know or can identify.

Because Indonesian demonstratives usually come after the noun.

So:

• film itu = that film
• buku ini = this book
• rumah itu = that house

This is different from English, where this/that comes before the noun.

A useful basic pattern is:

• noun + ini = this noun
• noun + itu = that noun

Yes. Film is a normal Indonesian word, borrowed from English and Dutch usage long ago.

It means:

• film
• movie

In everyday Indonesian, film is very common.

Jelek usually means bad, ugly, or not good-looking / poor in quality, depending on context.

With film, it means the movie is bad or poor quality.

Examples:

• Tulisanmu jelek. = Your handwriting is bad/ugly.
• Bajunya jelek. = The clothes are ugly.
• Film itu jelek. = That film is bad.

So jelek can refer both to appearance and quality.

Yes, often you can.

• Film itu jelek = everyday, natural, conversational
• Film itu buruk = also means the film is bad, but sounds a bit more formal or literary

In casual speech, jelek is very common.
If you are talking about reviews, writing, or more formal language, buruk may sound more polished.

Because jelek is the predicate adjective in the sentence.

The structure is:

• Film itu = subject
• jelek = predicate

So Indonesian word order here is:

• Subject + adjective

That gives:

• Film itu jelek

This is the normal way to say That film is bad.

Yes, but it usually means something different.

• Film itu jelek = That/The film is bad
  This is a complete sentence.

• film jelek = a bad film / bad film
  This is usually just a noun phrase, not a full sentence.

So:

• Saya menonton film jelek. = I watched a bad film.
• Film itu jelek. = That film is bad.

This is an important difference.

No, that sounds unnatural.

Adalah is sometimes used as a linking word, but generally not before adjectives like jelek.

So you should say:

• Film itu jelek

Not:

• Film itu adalah jelek

Adalah is more commonly used in formal definitions or identifications, especially with nouns:

• Indonesia adalah negara besar. = Indonesia is a big country.

Even then, it is often optional in everyday speech.

Use tidak before the adjective.

So:

• Film itu tidak jelek. = That film is not bad.

Basic pattern:

• tidak + adjective
• tidak + verb

Examples:

• Dia tidak tinggi. = He is not tall.
• Saya tidak tahu. = I do not know.

Do not use bukan here.
Bukan is mainly used to negate nouns or noun phrases, not adjectives.

You have two common options.

1. Intonation only

   • Film itu jelek? = Is that film bad?

2. Add apakah for a clearer question

   • Apakah film itu jelek? = Is that film bad?

In casual speech, intonation alone is very common.

A simple approximation is:

• film → similar to English film
• itu → ee-too
• jelek → roughly juh-lek or jeh-lek

A few tips:

• j in Indonesian sounds like English j in job
• e in jelek can sound like a soft uh/e sound, depending on accent
• stress in Indonesian is usually not as strong as in English

A rough full pronunciation:

• film ee-too juh-lek

It is neutral and very natural in everyday Indonesian.

• Film itu jelek sounds normal in conversation.
• It is not rude just because it is direct, though of course calling a movie jelek is a negative opinion.

If you wanted to sound slightly more formal, you might say:

• Film itu buruk

But jelek is perfectly standard and common.