Γιατί έχεις τόσα βιβλία στο τραπέζι;

Yes. Γιατί can mean both why and because in Greek.

• In a question, as here, it means why:
  • Γιατί έχεις τόσα βιβλία στο τραπέζι; = Why do you have so many books on the table?
• In an answer, it can mean because:
  • Γιατί διαβάζω. = Because I’m studying / reading.

You understand which meaning it has from the context.

Έχεις is the 2nd person singular form of the verb έχω (to have).

So:

• έχω = I have
• έχεις = you have
• έχει = he/she/it has

In this sentence, the speaker is talking to one person informally, so έχεις is the correct form.

Yes. έχεις is used for you singular, informal.

If you wanted to speak politely or to more than one person, you would use έχετε:

• Γιατί έχετε τόσα βιβλία στο τραπέζι;

That can mean:

• Why do you have so many books on the table? (polite singular)
• Why do you all have so many books on the table? (plural)

Τόσα means so many / that many.

It often suggests surprise, emphasis, or reaction:

• τόσα βιβλία = so many books

By contrast, πολλά βιβλία just means many books and is more neutral.

So:

• Γιατί έχεις τόσα βιβλία στο τραπέζι; sounds like Why do you have so many books on the table?
• Γιατί έχεις πολλά βιβλία στο τραπέζι; would sound more like Why do you have many books on the table?, with less emotional emphasis.

Because βιβλία is neuter plural, and τόσος changes form to match the noun.

The forms are:

• masculine plural: τόσοι
• feminine plural: τόσες
• neuter plural: τόσα

Since:

• singular: το βιβλίο
• plural: τα βιβλία

the correct form is:

• τόσα βιβλία

This is adjective agreement: the word meaning so many must match the gender and number of books.

Βιβλίο is a common neuter noun ending in -ο. Its plural is:

• το βιβλίο = the book
• τα βιβλία = the books

Many neuter nouns form the plural in -ια.
So βιβλία is the normal plural form.

Good question. Στο is the contraction of:

• σε + το = στο

The preposition σε can cover several meanings that English separates into in, at, to, and sometimes on, depending on context.

So:

• στο τραπέζι here means on the table

Greek often uses σε where English chooses a more specific preposition. You learn the natural combinations by exposure.

Because Greek often does not use the article in this kind of phrase when speaking generally about quantity.

So:

• τόσα βιβλία = so many books

You could sometimes see an article in other contexts, but here the article is not needed.
The phrase sounds natural without it.

The order is:

• Γιατί = why
• έχεις = do you have / you have
• τόσα βιβλία = so many books
• στο τραπέζι = on the table

So literally it is something like:

• Why have-you so-many books on-the-table?

This is a very natural Greek word order.
Greek word order is more flexible than English, but this version is standard and clear.

Yes. Greek allows more flexibility than English.

For example, you might also hear:

• Γιατί έχεις στο τραπέζι τόσα βιβλία;

This still means the same thing, but the placement can shift the focus a little.
The original version,

• Γιατί έχεις τόσα βιβλία στο τραπέζι; is the most straightforward and neutral.

Greek uses the simple present έχεις, and English uses do-support to form the question:

• Greek: έχεις
• English: do you have

Greek does not need an extra word like do to make a question.
The sentence becomes a question through:

1. the question word Γιατί
2. intonation
3. the Greek question mark at the end

So έχεις simply means you have, and in English that becomes do you have in a question.

In Greek, the symbol ; is used as the question mark.

So:

• Greek ; = English ?

That means:

• Γιατί έχεις τόσα βιβλία στο τραπέζι; is a question, even though to an English speaker it may look like a semicolon.

A rough pronunciation is:

• Yia-TI E-hees TO-sa vee-VLEE-a sto tra-PE-zi?

A few helpful notes:

• γιατί stress on the last syllable: -τί
• έχεις sounds roughly like EH-hees
• βιβλία has the stress on -λί-
• τραπέζι has the stress on -πέ-

The stress marks in Greek are important and should be pronounced.

Usually βιβλία just means books, but in context it can sometimes refer to school books or textbooks too.

If the situation is a classroom or studying, a Greek speaker may understand βιβλία as:

• books in general
• schoolbooks
• textbooks

The exact meaning depends on context.

Yes, very easily.

Because of Γιατί and especially τόσα (so many), the sentence can sound:

• curious
• surprised
• slightly annoyed
• playful

For example, depending on tone, it might mean:

• Why do you have so many books on the table?
• Why on earth do you have so many books on the table?

The grammar stays the same, but the speaker’s tone changes the feeling a lot.