Buku kulit keras itu tebal.

In Malay, demonstratives such as ini and itu normally come after the noun phrase they modify.

• buku itu = that book
• rumah itu = that house
• buku kulit keras itu = that hardcover book

So itu does not just attach to buku alone here; it comes after the whole noun phrase buku kulit keras.

Malay often uses a zero copula in simple descriptive sentences. That means there is no separate word for is/am/are before an adjective.

So:

• Buku itu tebal = That book is thick
• Rumah itu besar = That house is big

Using adalah here would sound unnatural in normal everyday Malay. With adjectives like tebal, Malay usually just puts the subject first and the adjective after it.

Because tebal is the predicate of the sentence: it tells you something about the subject.

The structure is:

• Buku kulit keras itu = the subject
• tebal = what is being said about it

So the sentence works like:

• [That hardcover book] [is thick]

Even though adjectives often come after nouns in Malay, this is slightly different: here tebal is not inside the noun phrase, but is the main description of the subject.

Yes, kulit can literally mean skin, but it also has broader meanings such as cover, outer layer, or peel, depending on context.

In book-related language:

• kulit can refer to the cover
• kulit keras literally means hard cover

So buku kulit keras means hardcover book.

This is a normal Malay expression, not a weird literal sentence about a book made of skin.

Because kulit keras here is functioning as part of a compound noun, not as a separate descriptive clause.

Compare:

• buku kulit keras = hardcover book
• buku yang tebal = a book that is thick / a thick book

You use yang when introducing an adjective or relative-style modifier in a more explicit way. But in a fixed type expression like buku kulit keras, yang is not needed.

In this sentence, tebal describes the whole book, not just the cover.

So:

• Buku kulit keras itu tebal = That hardcover book is thick

If you wanted to say the cover is hard, you could say something like:

• Kulit buku itu keras = The cover of that book is hard

That is a different sentence structure and a different meaning.

This is a very useful distinction.

• Buku kulit keras itu tebal = That hardcover book is thick

  • tebal is the predicate
  • the sentence is making a statement

• buku tebal itu = that thick book

  • tebal is inside the noun phrase
  • it helps identify which book you mean

So in the original sentence, tebal is the main description being asserted. In buku tebal itu, it is just part of the noun phrase.

Malay does not have articles that work like English the and a.

Whether a noun is definite or indefinite is usually understood from context, or shown in other ways such as with itu.

For example:

• buku = book / a book / the book, depending on context
• buku itu = that book, often effectively definite
• sebuah buku = a book, with a classifier

So Malay does not need a separate word exactly matching English articles.

Not normally, if you mean hardcover book.

Buku kulit keras is the natural expression because kulit keras specifically refers to a hard cover or hard binding. Buku keras would sound odd or unclear, as if you were saying the book itself is physically hard.

So for hardcover book, use:

• buku kulit keras

Yes, it is natural and grammatical Malay.

A speaker might also say simpler versions depending on context, such as:

• Buku itu tebal = That book is thick
• Itu buku kulit keras = That is a hardcover book

But Buku kulit keras itu tebal is a normal sentence if you want to talk specifically about that hardcover book and say that it is thick.