Ova keramika je lijepa.

Because ova is the feminine singular form of this.

In Croatian, words like this change form to match the noun’s gender and number:

• ovaj = masculine singular
• ova = feminine singular
• ovo = neuter singular

Since keramika is a feminine singular noun, the correct form is ova keramika.

A very common clue is the ending -a. Many Croatian nouns ending in -a are feminine.

So:

• keramika → feminine
• nominative singular form → keramika

This is why both the demonstrative (ova) and the adjective (lijepa) also appear in feminine singular form.

Because adjectives in Croatian must agree with the noun they describe in gender, number, and case.

Here, keramika is:

• feminine
• singular
• nominative

So the adjective must also be feminine singular nominative:

• masculine: lijep
• feminine: lijepa
• neuter: lijepo

That is why the sentence says Ova keramika je lijepa.

It is in the nominative case.

Why? Because keramika is the subject of the sentence:

• Ova keramika = the thing being talked about
• je lijepa = what is being said about it

In simple X is Y sentences, the subject is normally in the nominative.

In standard Croatian, je is the normal present-tense form of to be for he/she/it is.

So:

• Ova keramika je lijepa = This pottery/ceramic is beautiful

Unlike some languages, Croatian usually does not omit the verb to be in ordinary present-tense statements like this.

So Ova keramika lijepa would generally sound incomplete or nonstandard in normal usage.

Because lijepa is a predicate adjective: it describes the subject after the verb to be.

In Croatian, predicate adjectives still agree with the subject:

• Ovaj stol je lijep.
• Ova keramika je lijepa.
• Ovo selo je lijepo.

So even after je, the adjective changes form to match the subject.

It depends on context.

Keramika can refer to things like:

• ceramics / pottery as a material or type of craft
• ceramic ware
• sometimes a ceramic object or ceramic work, depending on context

Grammatically, though, it is treated here as a singular feminine noun. So even if English might sometimes use a plural-like idea such as ceramics, Croatian still uses singular grammar in this sentence.

Yes, Croatian word order is fairly flexible, though Ova keramika je lijepa is the most neutral order.

Other orders are possible for emphasis, for example:

• Lijepa je ova keramika. → puts more focus on beautiful
• Ova je keramika lijepa. → can contrast this pottery with something else

So the basic meaning can stay similar, but the emphasis changes.

Croatian has no articles like English a or the.

So Croatian often expresses definiteness through context, word order, or words like demonstratives:

• keramika = pottery / ceramics
• ova keramika = this pottery / this ceramic piece

Here, ova already makes the noun specific, so no article is needed.

A simple approximation is:

• lijepa ≈ LYEH-pa

The tricky part is lj, which is a single Croatian sound, similar to the lli in some pronunciations of million, though not exactly the same in every English accent.

Also:

• je is pronounced roughly like ye
• ova ≈ OH-va
• keramika ≈ keh-RAH-mee-ka

So the whole sentence is approximately:

• OH-va keh-RAH-mee-ka ye LYEH-pa

Yes, but it means something slightly different.

• ova keramika = this pottery / this ceramic item (near the speaker, or more immediate)
• ta keramika = that pottery or sometimes that particular pottery already known in the conversation

So ova and ta are not interchangeable in every context. Ova points to something closer or more directly present in the speaker’s focus.