Керамика хрупкая.

In Russian, the verb to be is usually left out in the present tense.

So:

• Керамика хрупкая. = Ceramic/Ceramics is fragile.
• Literally, it is more like Ceramic fragile.

This is completely normal Russian. If you wanted the past or future, you would use forms of быть:

• Керамика была хрупкой. = The ceramic was fragile.
• Керамика будет хрупкой. = The ceramic will be fragile.

Because it has to agree with керамика.

Керамика is:

• feminine
• singular
• nominative

So the adjective also has to be feminine singular nominative, which gives хрупкая.

Compare:

• хрупкий — masculine
• хрупкая — feminine
• хрупкое — neuter
• хрупкие — plural

Russian adjectives change their endings to match the noun they describe.

The dictionary form is хрупкий.

Russian dictionaries usually list adjectives in the masculine singular nominative form. So you look up хрупкий, even if in the sentence you see хрупкая.

Here, керамика is singular.

In Russian, керамика often works like a material noun or a general category word, similar to English ceramic or ceramics depending on context.

So Керамика хрупкая can mean something like:

• Ceramic is fragile
• Ceramics are fragile
• Ceramic ware is fragile

Russian and English do not always divide these ideas the same way.

Both words are in the nominative form here.

• керамика = nominative singular feminine
• хрупкая = nominative singular feminine

That is because керамика is the subject, and хрупкая is a predicate adjective describing it.

Yes. Керамика хрупка is also grammatically correct.

Here is the difference:

• Керамика хрупкая — the full adjective; very common and natural in everyday speech
• Керамика хрупка — the short adjective; more literary, formal, or concise

For most learners, хрупкая is the safer and more neutral version to use in normal conversation.

It is pronounced:

кера́мика хру́пкая

The stress falls on:

• ра́ in кера́мика
• хру́ in хру́пкая

A rough English-style guide would be:

kee-RA-mi-ka KHROOP-ka-ya

But it is best to learn it from the stressed Russian forms rather than rely too much on English spelling.

Russian has no articles.

So керамика can mean:

• ceramic
• the ceramic
• a ceramic material
• ceramics

The exact meaning depends on context. Russian uses context, word order, and sometimes other words to show whether something is definite or indefinite.

Yes, it can.

• Керамика хрупкая. = a full sentence: Ceramic is fragile.
• Хрупкая керамика = usually a noun phrase: fragile ceramic(s) or fragile pottery

So in your original sentence, the order helps show that this is a statement, not just a noun phrase.