Η επιχείρηση είναι μικρή.

Η is the feminine singular definite article, so here it means the.

So:

• η επιχείρηση = the business / the company

Greek articles change for gender, number, and case, so η specifically matches a feminine singular noun in the nominative case.

No. In Greek, nouns have grammatical gender, and επιχείρηση is grammatically feminine.

That means words connected to it must also be feminine:

• η because the noun is feminine
• μικρή because the adjective must agree with the noun

This is grammar, not biological sex. A business is not literally female; it just belongs to the feminine noun class.

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

The noun επιχείρηση is:

• feminine
• singular
• nominative

So the adjective must also be feminine singular nominative:

• masculine: μικρός
• feminine: μικρή
• neuter: μικρό

Here, the correct form is μικρή.

Είναι is the present tense of to be for:

• he/she/it is
• they are

So in this sentence it means is.

A few forms of to be in Modern Greek are:

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

So Η επιχείρηση είναι μικρή literally follows the pattern:

• The business is small

Because Greek does not need a separate subject pronoun here. The subject is already stated:

• Η επιχείρηση = the business

So Greek simply says:

• Η επιχείρηση είναι μικρή

You would only add a pronoun in special cases, usually for emphasis or contrast. In normal sentences, Greek often leaves pronouns out when they are not needed.

A helpful approximate pronunciation is:

ee e-pee-HEE-ree-see EE-ne mee-KREE

A few notes:

• Η sounds like ee
• επιχείρηση has the stress on χεί
• είναι sounds like EE-ne
• μικρή has the stress on the last syllable

A slightly more careful guide:

• Η = ee
• επιχείρηση = e-pee-HEE-ree-see
• είναι = EE-ne
• μικρή = mee-KREE

The Greek χ in επιχείρηση is not like English ch. Before ι, it is a softer sound, somewhat like the ch in German ich.

Because in Modern Greek, several different spellings are pronounced the same or almost the same as ee.

For example:

• η
• ι
• ει
• οι
• υ

These are all usually pronounced like ee in modern speech.

So in this sentence:

• Η sounds like ee
• the ει in είναι also sounds like ee

This is normal in Modern Greek spelling. The spelling preserves older historical distinctions, even though the pronunciation has merged.

Because here μικρή is being used as a predicate adjective:

• Η επιχείρηση είναι μικρή = The business is small

It is not directly attached to the noun; it comes after είναι and describes the subject.

Compare:

• η μικρή επιχείρηση = the small business
  This is an adjective directly modifying the noun.

• η επιχείρηση είναι μικρή = the business is small
  This is a full sentence with is.

So both are correct, but they do different jobs.

Not completely. Greek word order is more flexible than English word order.

The neutral, straightforward order is:

• Η επιχείρηση είναι μικρή

But Greek can move words for emphasis, for example:

• Μικρή είναι η επιχείρηση

This still means roughly the same thing, but it emphasizes small.

For a beginner, the given order is the safest and most natural one to use first.

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

You can tell from:

• η = feminine singular nominative article
• επιχείρηση = nominative singular noun

Also, the adjective μικρή is nominative singular feminine as well, because after είναι, predicate adjectives agree with the subject.

So both the noun phrase and the adjective match as:

• feminine
• singular
• nominative

In a normal sentence like this, you should use είναι.

So:

• Η επιχείρηση είναι μικρή = correct, normal sentence

If you remove είναι, the result does not sound like a normal complete sentence for standard everyday Greek. You might sometimes see omission in headlines, notes, or very compressed styles, but as a learner, keep είναι.

Yes. Depending on context, επιχείρηση can mean:

• business
• company
• enterprise
• sometimes even operation

In this sentence, the exact English translation depends on the context you were given. Grammatically, the sentence works the same way no matter which of those meanings is intended.