Cincin itu mempunyai berlian.

In Malay, demonstratives like ini (this) and itu (that) usually come after the noun:

• cincin itu = that ring / the ring
• buku ini = this book

So Malay uses noun + itu/ini, not that + noun like English.

It can feel like either one, depending on context.

• cincin itu can mean that ring
• It can also work like the ring when you are talking about a specific ring already known in the conversation

Malay does not have a separate word exactly like English the, so itu often helps make a noun definite.

Mempunyai means to have / to possess. It is more formal or written-sounding.

• Cincin itu mempunyai berlian. = formal: The ring has a diamond / diamonds.
• Cincin itu ada berlian. = more everyday and conversational

Both are understandable, but ada is very common in speech.

The base is punya, which is related to having or belonging to.

When Malay adds the prefix mem- and the suffix -i, it becomes mempunyai, a verb meaning to have.

So:

• punya = have / belong to / own
• mempunyai = to possess, to have

For many learners, it is enough at first just to recognize mempunyai as a formal verb meaning have.

Malay does not normally use articles like a, an, or the the way English does.

So:

• berlian can mean a diamond, the diamond, or diamonds
• the exact meaning depends on context

If you really want to emphasize one diamond, Malay can use a classifier, such as:

• sebutir berlian = a diamond (literally one piece/grain of diamond, a common classifier for small round objects or gems)

But in many normal sentences, Malay simply says berlian.

It is not explicitly marked. Malay nouns usually do not change form for singular vs. plural.

So berlian could mean:

• a diamond
• diamonds

Context tells you which one is meant.

If Malay wants to make the plural very clear, it can use reduplication:

• berlian-berlian = diamonds

But that is only used when the speaker wants to stress plurality.

Yes, it is grammatical, but it sounds a bit formal.

A more everyday way to say it would often be:

• Cincin itu ada berlian.

If you are learning textbook or formal Malay, mempunyai is perfectly fine. If you want speech that sounds more casual and natural, ada is often preferred.

Yes. Malay often puts one noun after another to describe it.

• cincin berlian = diamond ring

That is slightly different from:

• cincin itu mempunyai berlian = the ring has a diamond / diamonds

So:

• cincin berlian describes the type of ring
• mempunyai berlian tells you something the ring possesses

In very colloquial Malay or Indonesian-influenced speech, you may hear punya used in ways related to possession, but in standard Malay for this sentence, mempunyai or ada is better.

So the safer choices are:

• Cincin itu mempunyai berlian. = formal
• Cincin itu ada berlian. = common spoken style

Using punya directly here may sound nonstandard or dialectal, depending on context.

A simple approximate pronunciation is:

• məm-pu-nyai

A rough English-friendly guide:

• mem like muhm
• pu like poo
• nyai with ny like the ny in canyon, followed by something like eye

So it sounds roughly like muhm-poo-nyeye.

The ny sound is important in Malay and appears in many words.

You could, but it would usually sound less natural unless you are speaking very generally or in a formal style.

Compare:

• Cincin itu mempunyai berlian. = That/The ring has a diamond.
• Cincin mempunyai berlian. = A ring / rings have diamonds or a more general statement

Adding itu makes the ring specific.

Yes. The basic order here is:

• Cincin itu = subject
• mempunyai = verb
• berlian = object

So it follows a normal Subject–Verb–Object pattern, much like English:

• The ring
  • has
    • a diamond

That makes this sentence quite straightforward for English speakers once they get used to itu coming after the noun.