Τα τέλη κυκλοφορίας είναι μεγάλα.

• Τα = the definite article, neuter plural
• τέλη = a noun, neuter plural
• κυκλοφορίας = a noun in the genitive singular
• είναι = the verb to be
• μεγάλα = an adjective, neuter plural

So the basic structure is:

The fees/taxes of circulation are large/high.

In more natural English, this usually refers to vehicle road tax / circulation tax being high.

Because τέλη is a neuter plural noun, so it takes the neuter plural article τα.

Greek articles must agree with the noun in gender, number, and case:

• masculine plural: οι
• feminine plural: οι
• neuter plural: τα

Since τέλη is neuter plural, τα is the correct article.

The singular is το τέλος.

However, this is a word with a broad range of meanings depending on context. In general Greek, τέλος can mean end, but in administrative or financial contexts, τέλη often means fees, charges, or taxes.

So here:

• το τέλος = a fee / charge / tax
• τα τέλη = fees / charges / taxes

In this specific phrase, τα τέλη κυκλοφορίας is a fixed expression meaning vehicle circulation tax / road tax.

Κυκλοφορίας is the genitive singular of η κυκλοφορία.

The genitive here shows a relationship like of circulation or for circulation/use on the road. Greek often uses this pattern where English might use a compound noun.

So:

• η κυκλοφορία = circulation / traffic / movement
• της κυκλοφορίας = of circulation

In τέλη κυκλοφορίας, the genitive tells you what kind of fees these are: circulation fees, meaning the tax/fees connected with a vehicle being allowed to circulate on the roads.

Because Greek often leaves out the article in set expressions like this, especially in administrative or official-style noun combinations.

So τέλη κυκλοφορίας is treated as a standard expression, similar to:

• φόρος εισοδήματος = income tax
• άδεια οδήγησης = driving licence
• στάση λεωφορείου = bus stop

You could think of it as a compact label: circulation fees.

In Modern Greek, είναι is used for both:

• he/she/it is
• they are

So the form does not change between third person singular and third person plural.

Examples:

• Είναι μεγάλο. = It is big.
• Είναι μεγάλα. = They are big.

The adjective usually makes the number clearer here, because μεγάλα is plural.

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

The noun τέλη is neuter plural, so the adjective must also be neuter plural:

• masculine plural: μεγάλοι
• feminine plural: μεγάλες
• neuter plural: μεγάλα

So:

• τα τέλη → μεγάλα

Literally, yes: μεγάλος / μεγάλη / μεγάλο means big / large.

But in this sentence, the natural meaning is more like:

• high
• expensive
• substantial

So Τα τέλη κυκλοφορίας είναι μεγάλα is best understood as:

• The road tax is high
• The circulation fees are high

This is very common in Greek: a word that literally means big/large can also mean high when talking about costs, amounts, fees, and similar things.

Grammatically, it is plural.

• τα τέλη = the fees / the taxes

But in English, we often translate this kind of expression with a singular mass noun like road tax. So depending on context, English may use either a plural or singular-style translation.

Greek, however, is clearly plural here, which is why the adjective is plural too:

• Τα τέλη ... είναι μεγάλα

Yes. Greek word order is more flexible than English.

The neutral order here is:

Τα τέλη κυκλοφορίας είναι μεγάλα.

But you could also hear:

• Μεγάλα είναι τα τέλη κυκλοφορίας.
• Τα τέλη κυκλοφορίας μεγάλα είναι. (less neutral, more marked)

Changing the order usually changes emphasis, not the basic meaning.

For example:

• Μεγάλα είναι τα τέλη κυκλοφορίας puts extra focus on μεγάλα.

A simple pronunciation guide is:

Ta TEH-lee kee-klo-foh-REE-as EE-ne MEH-gha-la

A few helpful notes:

• τέλη has the stress on the first syllable: ΤΕ-λη
• κυκλοφορίας has the stress on -ρί-
• είναι is pronounced roughly EE-ne
• μεγάλα has the stress on γά

Also remember that Greek stress marks are important and should be learned with the word.

With τα, the sentence refers to the circulation fees, but Greek often uses the definite article where English might still speak more generally.

So depending on context, it could mean:

• The road taxes are high
• Road taxes are high

Greek uses the definite article much more often than English, especially with general categories and familiar institutions.

Yes, υψηλά can also work, especially in more formal or administrative language.

Compare:

• μεγάλα = more everyday, very natural
• υψηλά = more formal, more like high

So both can be understood, but μεγάλα is very common in ordinary speech when talking about fees, prices, or costs.