Θέλεις κέτσαπ στο τοστ ή μουστάρδα;

Θέλεις means do you want?

It is the:

• 2nd person singular
• present tense
• of the verb θέλω = to want

So it is used when speaking to one person informally, like you want...?

If you were speaking politely or to more than one person, you would say Θέλετε instead.

Because they are loanwords or internationally shared food words:

• κέτσαπ = ketchup
• τοστ = toast / toasted sandwich
• μουστάρδα = mustard

Greek often adapts foreign words to Greek spelling and pronunciation. That is why they look familiar but are written in the Greek alphabet.

στο means in/on/to the, depending on context.

It is a contraction of:

• σε = in / on / to
• το = the

So:

• σε το → στο

In this sentence, στο τοστ means something like in/on the toast or more naturally in English, with your toast/toasted sandwich.

Because στο τοστ tells you where the ketchup or mustard is going: on/in the toast.

The two choices are the condiments:

• κέτσαπ
• μουστάρδα

So the structure is basically:

Do you want ketchup on the toast, or mustard?

In the second option, Greek leaves out the repeated phrase στο τοστ because it is already understood.

Fuller version:

• Θέλεις κέτσαπ στο τοστ ή μουστάρδα στο τοστ;

But that sounds repetitive, so Greek normally omits the repeated part.

In Greek, foods and condiments are often used without an article when talking about them in a general, indefinite way.

So:

• Θέλεις κέτσαπ; = Do you want ketchup?
• Θέλεις μουστάρδα; = Do you want mustard?

This is similar to English, where we also usually do not say a ketchup or a mustard in this kind of sentence.

ή means or.

It has an accent to distinguish it from η, which means the for feminine nouns.

So:

• ή = or
• η = the

This is a very common point for learners, because they look almost identical.

A simple pronunciation guide is:

THEH-lis KETCH-ap sto tost ee moo-STAR-tha?

A slightly more Greek-like version:

• Θέλεις = THEH-lees
• κέτσαπ = KETCH-ap
• στο = sto
• τοστ = tost
• ή = ee
• μουστάρδα = moo-STAR-tha

Notes:

• θ sounds like th in think
• δ sounds like th in this

Yes. Θέλεις is informal singular, used with:

• a friend
• a child
• someone you know well
• one person in a casual situation

For polite singular or plural, use:

• Θέλετε κέτσαπ στο τοστ ή μουστάρδα;

That can mean:

• Do you want ketchup on the toast or mustard? said politely to one person
• or the same thing said to more than one person

In Greek, τοστ often means a toastie / toasted sandwich, not just a slice of toasted bread.

So depending on context, στο τοστ may sound more like:

• in the toasted sandwich
• on the sandwich
• with the toastie

In everyday Greek, τοστ is commonly used for a simple toasted sandwich.

Yes, Greek word order is flexible.

This sentence:

• Θέλεις κέτσαπ στο τοστ ή μουστάρδα;

is natural and clear.

But you could also hear:

• Θέλεις στο τοστ κέτσαπ ή μουστάρδα;
• Θέλεις κέτσαπ ή μουστάρδα στο τοστ;

These all mean roughly the same thing, though the emphasis may shift a little.

The original version sounds like:

• first option: ketchup on the toast
• second option: or mustard?

They are functioning as the things wanted, so they are effectively the direct objects of Θέλεις.

In practice:

• κέτσαπ does not visibly change here
• μουστάρδα is also in its normal dictionary form

For many everyday nouns, especially loanwords and mass nouns like condiments, learners often do not notice much case change in sentences like this. But grammatically, they are the objects of the verb.

You could translate it literally that way, but it may sound odd in natural English.

A better natural translation would usually be:

• Do you want ketchup or mustard in your toastie?
• Do you want ketchup or mustard on the toast?
• Do you want ketchup or mustard with your toasted sandwich?

The exact English wording depends on what τοστ refers to in the situation.

A few simple answers are:

• Κέτσαπ. = Ketchup.
• Μουστάρδα. = Mustard.
• Θέλω κέτσαπ. = I want ketchup.
• Θέλω μουστάρδα. = I want mustard.
• Δεν θέλω τίποτα. = I don’t want anything.
• Και τα δύο. = Both.

These are all natural short replies.