Langkah pencegahan itu penting.

In Malay, you often do not need a verb like is/are in simple sentences where one thing is being described.

So:

• Langkah pencegahan itu penting
• literally: That preventive measure / those preventive measures important
• natural English: That preventive measure is important or Those preventive measures are important

This is very normal in Malay. The adjective penting can act as the predicate by itself.

You may sometimes see adalah, but in everyday Malay it is often unnecessary here.
So Langkah pencegahan itu penting is a very natural sentence.

It breaks down like this:

• langkah = step, measure
• pencegahan = prevention
• langkah pencegahan = preventive step / preventive measure / prevention measure

So langkah pencegahan is a noun phrase meaning a measure taken to prevent something.

In English, we often turn this into a more natural phrase like:

• preventive measures
• preventive action
• a preventive step

Pencegahan comes from the root cegah, which means prevent.

The noun is formed with the circumfix:

• peN- ... -an

So:

• cegah = to prevent
• pencegahan = prevention

This pattern is very common in Malay. It often turns a root into a noun referring to:

• the act
• the process
• the concept

A few similar examples:

• bangun = wake up / build → pembangunan = development
• didik = educate → pendidikan = education

So pencegahan is the noun prevention.

Itu usually means that, but in sentences like this it often works more like a definite marker, similar to the or that depending on context.

So:

• langkah pencegahan = preventive measure(s) in general
• langkah pencegahan itu = that preventive measure / those preventive measures / the preventive measure(s)

In Malay, demonstratives like ini and itu usually come after the noun:

• buku ini = this book
• rumah itu = that house
• langkah pencegahan itu = that preventive measure / those preventive measures

That post-noun position is normal Malay word order.

Yes. A bare Malay noun is often not marked for number. That means langkah can mean:

• a measure
• measures

The exact number depends on context.

So Langkah pencegahan itu penting could mean:

• That preventive measure is important
• Those preventive measures are important
• The preventive measure is important
• The preventive measures are important

If Malay speakers want to make plurality especially clear, they may use reduplication:

• langkah-langkah pencegahan = preventive measures

But very often, Malay leaves number to context.

Not necessarily better—just more explicitly plural.

Compare:

• Langkah pencegahan itu penting
  = can be singular or plural, depending on context

• Langkah-langkah pencegahan itu penting
  = clearly plural: Those preventive measures are important

Malay often avoids reduplication when the context already makes plurality clear. So the original sentence is perfectly natural.

Yes, you can, but the meaning changes slightly.

• Langkah pencegahan itu penting = That/The preventive measure is important or Those/The preventive measures are important
• Langkah pencegahan penting = Preventive measures are important or Prevention measures are important

Without itu, the phrase sounds more general and less specifically tied to a particular measure or set of measures.

So:

• with itu → more specific
• without itu → more general

Yes.

• langkah pencegahan ini = this preventive measure / these preventive measures
• langkah pencegahan itu = that preventive measure / those preventive measures

The difference is the same basic one as this/these versus that/those in English.

So:

• Langkah pencegahan ini penting = This/These preventive measure(s) are important
• Langkah pencegahan itu penting = That/Those preventive measure(s) are important

Because penting is the predicate adjective here.

Sentence structure:

• Langkah pencegahan itu = the subject
• penting = important

So the pattern is:

• [noun phrase] + [adjective]

This is a very common Malay sentence pattern.

Also note the difference between:

1. Predicate use

   • Langkah pencegahan itu penting
   • That preventive measure is important

2. Attributive use

   • langkah penting
   • an important step

In Malay, adjectives usually come after the noun when they directly modify it:

• langkah penting = important step
• rumah besar = big house

But in your sentence, penting is not modifying langkah inside the noun phrase. It is stating something about the whole subject.

Yes, it is grammatically possible, but it is usually less natural in ordinary speech.

• Langkah pencegahan itu penting = the most natural everyday version
• Langkah pencegahan itu adalah penting = more formal, more emphatic, or sometimes influenced by formal writing style

In many cases, Malay does not need adalah before an adjective predicate.

A useful guideline:

• For simple descriptive statements, leaving out adalah is usually best.
• Using adalah can sound more formal or stiff if it is not needed.

So learners should generally prefer:

• Langkah pencegahan itu penting

A simple pronunciation guide:

• Langkah ≈ LAHNG-kah
• pencegahan ≈ pen-cheh-GA-han
• itu ≈ ee-too
• penting ≈ pen-TING

A few notes:

• ng in langkah and penting is like the sound at the end of English sing
• c in Malay is pronounced like ch
• Malay spelling is generally quite phonetic compared with English

So the full sentence is roughly:

LAHNG-kah pen-cheh-GA-han ee-too pen-TING

It is neutral and standard. It works well in:

• conversation
• school writing
• news-style language
• public information contexts

Because the sentence is short and clear, it sounds especially suitable for formal or informational contexts such as health advice, safety notices, or official statements.

So it is not slangy, and it is not unusually stiff either. It is just good standard Malay.