Η δικαιολογία δεν είναι καλή.

Η is the definite article for a feminine singular noun in the nominative case. It means the.

Here, δικαιολογία is a feminine singular noun, so it takes η:

• η δικαιολογία = the excuse / the justification

So Η δικαιολογία is the subject of the sentence.

δικαιολογία is in the nominative singular because it is the subject of the sentence.

The basic pattern is:

• Η δικαιολογία = the excuse / the justification

If the noun had a different role in the sentence, its form might change. For example, Greek nouns change form depending on case. But here it is simply the thing being talked about, so nominative singular is the correct form.

δεν is the normal Greek word for not before a verb.

So:

• είναι = is
• δεν είναι = is not

In this sentence:

• Η δικαιολογία δεν είναι καλή = The excuse is not good

A useful thing to remember is that δεν usually comes directly before the verb.

είναι is the 3rd person singular of the verb είμαι (to be).

So it means:

• είμαι = I am
• είσαι = you are
• είναι = he/she/it is

Since the subject is η δικαιολογία (the excuse), Greek uses είναι = is.

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

Since δικαιολογία is:

• feminine
• singular
• nominative

the adjective must also be feminine singular nominative:

• καλός = good (masculine)
• καλή = good (feminine)
• καλό = good (neuter)

So:

• η δικαιολογία → feminine
• therefore καλή

Because this sentence uses είναι (to be) to link the subject to an adjective.

This is called a predicate adjective structure:

• Η δικαιολογία είναι καλή = The excuse is good

That is different from putting the adjective directly next to the noun:

• η καλή δικαιολογία = the good excuse

So:

• η καλή δικαιολογία = adjective directly describes the noun inside the noun phrase
• η δικαιολογία είναι καλή = the sentence says what the excuse is like

Yes, Greek word order is more flexible than English, though some orders are more neutral than others.

The most neutral order here is:

• Η δικαιολογία δεν είναι καλή.

You may also hear:

• Δεν είναι καλή η δικαιολογία.

This can sound a little more emphatic, like focusing on not good first.

Even though Greek allows flexibility, beginners should usually learn the neutral pattern first:

• subject + δεν + verb + adjective

No. In Modern Greek, Η / η is pronounced ee, like the ee in see.

So:

• Η is not an h sound
• it sounds like ee

In this sentence:

• Η δικαιολογία sounds roughly like ee thee-keh-oh-loh-YA

The exact pronunciation depends on the speaker, but the key point is that η is a vowel sound, not an English h.

A rough pronunciation is:

• thee-keh-oh-loh-YA

The stress falls on the last syllable:

• δικαιολογία

A slightly more careful breakdown is:

• δι = thee
• και = roughly keh or kay depending on how carefully it is pronounced in connected speech
• ο = o
• λο = lo
• γία = YA

For a learner, the most important thing is to hear that the stress is at the end.

The accent mark in Modern Greek shows which syllable is stressed.

So:

• δικαιολογία
• είναι
• καλή

Stress matters in Greek pronunciation and sometimes helps distinguish words. When learning vocabulary, it is very important to learn the accent together with the word.

Not always. δικαιολογία can mean things like:

• excuse
• justification
• pretext

The best translation depends on context.

For example:

• If someone gives a weak reason for doing something wrong, excuse fits well.
• If someone is trying to defend or justify an action, justification may fit better.

So the grammar of the sentence stays the same, but the most natural English meaning can vary by context.

In normal standard Modern Greek, no—you usually keep είναι in a sentence like this.

So:

• Η δικαιολογία δεν είναι καλή. = correct
• leaving out είναι would sound unnatural in standard Greek

Greek often omits subject pronouns, but not the verb to be in this kind of sentence.

Because the subject is already stated explicitly:

• Η δικαιολογία = the excuse

So Greek does not need to add a separate pronoun like it. The sentence literally works as:

• The excuse not is good

In natural English, we say:

• The excuse is not good

Greek often avoids unnecessary pronouns when the noun itself is already present.

The sentence follows this pattern:

• Article + noun + δεν + verb + adjective

More specifically:

• Η = the
• δικαιολογία = excuse / justification
• δεν = not
• είναι = is
• καλή = good

So the structure is:

• The excuse is not good

This is a very useful pattern for making simple descriptive sentences in Greek.