Το παλάτι είναι μεγάλο.

Παλάτι is neuter. That is why it uses the article το and the adjective form μεγάλο.

A useful pattern to notice is that many Greek nouns ending in -ι are neuter, though you still have to learn each noun individually.

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

Since παλάτι is neuter singular, the adjective must also be neuter singular:

• masculine: μεγάλος
• feminine: μεγάλη
• neuter: μεγάλο

So το παλάτι είναι μεγάλο is grammatically matched all the way through.

Είναι is a present-tense form of είμαι, meaning to be.

It can mean either:

• is
• are

The subject tells you which one is meant. Here the subject is singular, το παλάτι, so είναι means is.

Greek often leaves out subject pronouns when they are not necessary. English usually needs it is, but Greek can often just use the verb, especially when the subject is already clear.

In this sentence, the subject is explicitly stated as το παλάτι, so there is no need for a separate word meaning it.

Not as rigidly as in English. Greek word order is fairly flexible because endings give grammatical information.

Το παλάτι είναι μεγάλο is the most neutral and straightforward order for The palace is big.

Other orders are possible for emphasis, but this version is the standard one a learner should start with.

They are built differently:

• Το παλάτι είναι μεγάλο = The palace is big
• Το μεγάλο παλάτι = The big palace

In the first sentence, μεγάλο comes after είναι because it is a predicate adjective.

In the second phrase, μεγάλο goes directly with the noun because it is an attributive adjective.

Yes. The accent marks show which syllable is stressed, and correct stress matters in Greek.

In this sentence:

• παλάτι → stress on λά
• είναι → stress on εί
• μεγάλο → stress on γά

So the rhythm is roughly:

• pa-LA-ti
• EE-ne
• me-GHA-lo

A rough English-friendly guide is:

to pa-LA-ti EE-ne me-GHA-lo

A few notes:

• το sounds like to
• παλάτι has the stress on λά
• είναι has the stress on εί
• μεγάλο has the stress on γά
• the γ in μεγάλο is not a hard English g like in go; it is a softer sound, similar to the Spanish g in lago

Yes. Μεγάλο can mean big or large, depending on context. Both are natural translations here.

Sometimes related forms of μεγάλος can also mean great in other contexts, but in this sentence the basic meaning is simply big / large.

Normally, no. If you mean the palace, the article το is the normal and expected choice.

Greek uses the definite article very often, and leaving it out here would sound unnatural in ordinary speech.

Because it is the first word of the sentence. Greek capitalizes the beginning of a sentence just like English does.

If the same word appeared in the middle of a sentence, it would normally be written το.