Kubis ini lebih murah daripada sayur yang saya beli kemarin.

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

• kubis ini = this cabbage
• rumah itu = that house

So Kubis ini is the normal Indonesian word order, even though in English we say this cabbage.

Lebih ... daripada ... is a very common pattern for comparisons in Indonesian. It means more ... than ...

So here:

• lebih murah = cheaper / more cheap
• daripada = than

Together:

• lebih murah daripada sayur yang saya beli kemarin = cheaper than the vegetable(s) I bought yesterday

Other examples:

• lebih besar daripada = bigger than
• lebih cepat daripada = faster than

Daripada is the standard and safest choice in comparisons like this.

• lebih murah daripada ... = cheaper than ...

In everyday speech, some people also use dari in comparisons, but daripada is generally clearer and more standard in this kind of sentence.

So for learners, it is best to remember:

• lebih + adjective + daripada + noun/phrase

Sayur can be a little flexible in Indonesian.

It can mean:

• vegetable(s) in a general sense
• a vegetable dish, depending on context

In this sentence, sayur yang saya beli kemarin most naturally means the vegetable(s) I bought yesterday.

By contrast, kubis is specific: it means cabbage. So the sentence is comparing this cabbage with some other vegetable or vegetables bought yesterday.

Here yang introduces a relative clause. It works a bit like that, which, or that ... in English.

• sayur = vegetable(s)
• yang saya beli kemarin = that I bought yesterday

So:

• sayur yang saya beli kemarin = the vegetable(s) that I bought yesterday

A useful way to think about yang is that it connects a noun to extra information about that noun.

Examples:

• buku yang saya baca = the book that I read
• orang yang datang = the person who came

Both are possible, but saya beli is very common and natural in everyday Indonesian.

• saya beli = I buy / I bought
• saya membeli = also I buy / I bought, but a bit more formal or explicit

The base verb beli means buy. Indonesian often allows verbs to appear without extra verb endings or conjugation.

So:

• sayur yang saya beli kemarin sounds natural and conversational
• sayur yang saya membeli kemarin would sound wrong, because if you use membeli, the object usually follows directly, not before it in this structure

If you wanted a version with membeli, you would normally restructure the sentence.

Indonesian verbs do not change form for tense the way English verbs do.

So beli can mean:

• buy
• bought
• will buy

The time is usually understood from context or from time words such as:

• kemarin = yesterday
• sekarang = now
• besok = tomorrow

In this sentence, kemarin tells you the action happened in the past, so saya beli is understood as I bought.

Yes, kemarin means yesterday.

In this sentence, it modifies saya beli:

• sayur yang saya beli kemarin = the vegetable(s) that I bought yesterday

So kemarin tells us when the buying happened, not necessarily something about the vegetable itself.

Word-for-word, the phrase is roughly:

• sayur = vegetable
• yang = that/which
• saya beli = I bought
• kemarin = yesterday

Indonesian does not usually use articles like a, an, or the.

So a noun like kubis can mean:

• cabbage
• a cabbage
• the cabbage

The exact meaning depends on context.

In this sentence:

• Kubis ini clearly means this cabbage
• sayur yang saya beli kemarin is understood as the vegetable(s) I bought yesterday because the relative clause makes it specific

So Indonesian often leaves article meanings to context instead of marking them with separate words.

Yes. Murah means cheap or inexpensive, depending on the tone you want in English.

• murah = cheap / inexpensive
• lebih murah = cheaper / more inexpensive

English speakers sometimes prefer inexpensive because cheap can sound negative, but in Indonesian murah is usually neutral and simply refers to low price.

The sentence is already in a very natural order:

• Kubis ini lebih murah daripada sayur yang saya beli kemarin.

Some parts are fairly fixed:

• kubis ini is the normal noun + demonstrative order
• lebih murah daripada ... is the normal comparison pattern
• yang saya beli kemarin is the normal relative clause after sayur

You could sometimes change emphasis in speech, but for a learner this version is the best one to remember.

Yes. Indonesian nouns usually do not have a separate singular/plural form.

So sayur can mean:

• vegetable
• vegetables

The exact number depends on context.

If the speaker wants to make it clearly plural, they might say:

• sayur-sayur = vegetables

But in many real sentences, Indonesian leaves number unspecified unless it matters. So sayur yang saya beli kemarin could refer to one vegetable item or vegetables in general, depending on the situation.