Αυτή είναι μία κιλοβατώρα.

Yes. Αυτή means this here.

In this sentence, it is the feminine singular form of this, because κιλοβατώρα is a feminine noun in Greek.

Greek words like this change form depending on the gender and number of the noun:

• αυτός = this (masculine)
• αυτή = this (feminine)
• αυτό = this (neuter)

So Greek uses Αυτή because it matches κιλοβατώρα.

Because κιλοβατώρα is a feminine noun.

The word for one in Greek changes for gender:

• ένας = one (masculine)
• μία / μια = one (feminine)
• ένα = one (neuter)

Since κιλοβατώρα is feminine, you need the feminine form μία.

It can do both jobs.

In Greek, the same word can mean:

• one as a number
• a / an as an indefinite article

So μία κιλοβατώρα can mean either:

• one kilowatt-hour
• a kilowatt-hour

Usually the context tells you which meaning is intended.

They are basically the same word.

• μία is the more careful, fully accented form
• μια is very common in everyday Greek and sounds more natural in casual speech

So you may see both:

• μία κιλοβατώρα
• μια κιλοβατώρα

Both are correct.

Είναι means is or are.

It is the 3rd person singular/plural form of the verb είμαι = to be.

So:

• Αυτή είναι... = This is...
• Αυτοί είναι... = These are...

Greek uses the same form, είναι, for both he/she/it is and they are.

Yes, Greek word order is more flexible than English, but this order is the most straightforward and neutral.

The sentence follows a simple pattern:

• Αυτή = this
• είναι = is
• μία κιλοβατώρα = one/a kilowatt-hour

So the structure is basically:

This + is + a kilowatt-hour

Greek can sometimes move words around for emphasis, but for a learner, this sentence is the normal pattern to remember.

Because in Greek, every noun has a grammatical gender, and κιλοβατώρα is treated as feminine.

A useful clue is the ending -α, which is very often feminine in Greek.
So nouns ending in -α are often feminine, though not always.

Because κιλοβατώρα is feminine, other words around it must match:

• αυτή
• μία

This kind of agreement is very important in Greek.

A natural pronunciation is approximately:

af-TEE EE-ne MEE-a kee-lo-va-TO-ra

A slightly more connected pronunciation might sound like:

af-TI EE-ne MIA kee-lo-va-TO-ra

A few tips:

• Αυτή sounds like af-TEE
• είναι sounds like EE-ne
• μία sounds like MEE-a
• κιλοβατώρα has the stress on -τώ-: kee-lo-va-TO-ra

The accent marks show which syllable is stressed.

In this sentence:

• Αυτή → stress on -τή
• είναι → stress on εί-
• μία → stress on μί-
• κιλοβατώρα → stress on -τώ-

Stress matters in Greek pronunciation, so the accent marks are important to learn.

By itself, αυτή can sometimes be related to forms meaning she or her, but in this sentence it clearly means this.

Why? Because the sentence is introducing or identifying something:

• Αυτή είναι μία κιλοβατώρα.

That pattern strongly suggests This is a kilowatt-hour, not She is a kilowatt-hour.

So the context makes the meaning clear.

It is an international scientific/technical word, but it is fully used as a Greek noun.

It is built from parts corresponding to:

• κιλο- = kilo-
• βατ = watt
• ώρα = hour

So κιλοβατώρα means kilowatt-hour.

Even though it comes from scientific vocabulary used across languages, Greek treats it like a normal Greek noun.

Yes, definitely.

In Greek, gender affects several other words in the sentence, such as:

• demonstratives like this
• articles
• adjectives
• numbers like one

So if you learn κιλοβατώρα, it is best to learn it together with its gender:

• η κιλοβατώρα = the kilowatt-hour

That helps you remember that it is feminine and that forms like αυτή and μία go with it.

Normally, μία sounds better here.

Greek often uses ένας / μία / ένα in sentences where English uses a/an with a singular countable noun.

So:

• Αυτή είναι μία κιλοβατώρα. = natural
• Αυτή είναι κιλοβατώρα. = less natural in this basic identifying sense

For a beginner, it is safest to include μία here.

It is η.

So:

• η κιλοβατώρα = the kilowatt-hour

This is useful because the article helps you remember the noun’s gender:

• η = feminine singular

That matches the rest of the sentence:

• Αυτή
• μία
• κιλοβατώρα

All of them are feminine singular.