Klepsydra jest gotowa.

Because klepsydra is a feminine singular noun, and the adjective has to agree with it.

• gotowy = masculine singular
• gotowa = feminine singular
• gotowe = neuter singular or non-masculine-personal plural

So:

• Klepsydra jest gotowa. = correct
• Klepsydra jest gotowy. = incorrect, because the gender does not match

This kind of agreement is very important in Polish.

A very common clue in Polish is the ending -a. Most nouns ending in -a are feminine.

So klepsydra is treated as feminine, which is why the adjective is gotowa.

As always, there are exceptions in Polish, but here the pattern is straightforward:

• klepsydra → feminine
• therefore gotowa

It is in the nominative singular.

That is because klepsydra is the subject of the sentence — the thing being described as ready.

So the structure is:

• Klepsydra = subject, nominative
• jest gotowa = is ready

In this sentence, jest is normally used.

Polish often does not drop the verb to be in standard present-tense sentences like this one. So:

• Klepsydra jest gotowa. = normal and correct
• Klepsydra gotowa. = possible in some special contexts, but not the neutral standard version

The version without jest can sound more like:

• a headline
• a note
• a dramatic or elliptical statement

For a learner, the safest choice is: keep jest.

Here gotowa means ready.

Depending on context, Polish gotowy / gotowa / gotowe can also mean things like:

• prepared
• finished and ready
• all set

So jest gotowa can mean:

• is ready
• is prepared

The exact nuance depends on the situation.

Yes — besides meaning hourglass, klepsydra can also mean a funeral notice / obituary notice in Polish.

So context matters a lot.

For example:

• in a history, science, or object-related context, klepsydra usually means hourglass
• in a funeral or social context, it may mean a death notice

Grammatically, though, the sentence works the same way either way.

Because Polish does not have articles like a or the.

So klepsydra can mean:

• an hourglass
• the hourglass

Which one is meant depends on context.

That is very normal in Polish. English needs articles; Polish usually does not.

Yes, Polish word order is more flexible than English word order.

The neutral order here is:

• Klepsydra jest gotowa.

But you might also hear:

• Gotowa jest klepsydra.

That version is more marked or stylistic. It may sound like you are emphasizing gotowa or creating a more literary tone.

For most everyday situations, Klepsydra jest gotowa is the best choice.

You put nie before jest:

• Klepsydra nie jest gotowa. = The hourglass is not ready.

This is the standard way to negate to be in Polish:

• jest → nie jest

Roughly: klep-SY-dra

A more careful breakdown:

• klep like klep
• sy with a Polish y sound, not exactly the English ee
• dra as written

A rough English-style approximation would be:

• klep-SIH-drah

The stress is on the second-to-last syllable, which is very common in Polish:

• klep-SY-dra

You technically can, but it is not the normal neutral order.

It sounds more poetic, dramatic, or stylized. Polish allows this kind of rearrangement more than English, but not every possible order sounds equally natural in everyday speech.

So as a learner, it is best to remember:

• Klepsydra jest gotowa. = standard, neutral, natural

If you want to say The hourglasses are ready, you would say:

• Klepsydry są gotowe.

Here several things change:

• klepsydra → klepsydry = plural noun
• jest → są = is → are
• gotowa → gotowe = adjective agrees with the plural noun

So the pattern of agreement stays the same.