Η αγγελία είναι καλή.

A rough pronunciation is:

ee ahng-ye-LEE-ah EE-ne ka-LEE

A few helpful notes:

• Η sounds like ee
• αγγελία has the stress on -λί-
• είναι is usually pronounced EE-ne
• καλή has the stress on the last syllable

Also, γγ in αγγελία does not sound like normal English gg. Many learners hear something like ngy or ng + soft y.

Η is the definite article the.

In this sentence it is:

• feminine
• singular
• nominative

So it matches αγγελία, which is a feminine singular noun.

In Greek, every noun has a grammatical gender: masculine, feminine, or neuter.

αγγελία is a feminine noun. You can tell that here because it uses the article η.

A very good habit in Greek is to learn nouns with their article:

• η αγγελία = the ad / the advertisement

That helps you remember the gender automatically.

Because Greek adjectives must agree with the noun they describe.

Since αγγελία is:

• feminine
• singular
• nominative

the adjective must also be feminine singular nominative:

• καλός = masculine
• καλή = feminine
• καλό = neuter

So Η αγγελία είναι καλή is the correct match.

είναι is the present-tense form of είμαι, meaning to be.

Here it means is.

A useful thing to know: είναι can mean both is and are in Modern Greek. The subject tells you whether it is singular or plural.

Examples:

• Η αγγελία είναι καλή. = The ad is good.
• Οι αγγελίες είναι καλές. = The ads are good.

Because καλή is a predicate adjective after the verb είναι.

Greek, like English, normally says:

• Η αγγελία είναι καλή. = The ad is good.

Not:

• Η αγγελία είναι η καλή unless you mean something special like the good one

So in a basic sentence with to be + adjective, you usually do not put an article before the adjective.

Normally, in standard Modern Greek, no.

Greek usually keeps the verb to be in this kind of sentence:

• Η αγγελία είναι καλή.

Leaving it out may sound:

• poetic
• headline-like
• fragmented
• non-standard in ordinary speech

So for normal learning and normal conversation, keep είναι.

Yes. Greek word order is more flexible than English, although Η αγγελία είναι καλή is the most neutral version.

You may also hear:

• Είναι καλή η αγγελία.
• Καλή είναι η αγγελία.

These can shift the emphasis a bit. For example, starting with καλή may emphasize good.

But for a beginner, the safest default is:

• Η αγγελία είναι καλή.

This is a very important difference.

• Η αγγελία είναι καλή = The ad is good.
  A complete sentence.

• Η καλή αγγελία = the good ad
  Just a noun phrase, not a complete sentence.

So:

• article + noun + είναι + adjective = full sentence
• article + adjective + noun = noun phrase

Both the noun and the adjective are in the nominative here.

• Η αγγελία is nominative because it is the subject
• καλή is also nominative because it is a predicate adjective agreeing with the subject after είναι

So the full agreement is:

• η αγγελία = feminine singular nominative
• καλή = feminine singular nominative

The accent marks show which syllable is stressed.

• αγγελία
• είναι
• καλή

This is very important in Greek pronunciation.

Notice that Η has no accent. That is normal, because it is a one-syllable word.

Not always. Depending on context, αγγελία can mean things like:

• ad
• advertisement
• notice
• announcement

So the exact English choice depends on the situation. But grammatically, it behaves the same way in this sentence.

Both, but especially as a pattern.

This sentence gives you a very useful structure:

• Η/Ο/Το + noun + είναι + adjective

For example:

• Η αγγελία είναι καλή. = The ad is good.
• Το βιβλίο είναι καλό. = The book is good.
• Ο φίλος είναι καλός. = The friend is good.

This helps you practice:

• articles
• gender
• adjective agreement
• the verb είναι