Το παράσιτο είναι στα φύλλα.

Because παράσιτο is a neuter singular noun, so it takes the neuter singular definite article το in the nominative: το παράσιτο = the parasite.

In Greek, the article must agree with the noun in gender, number, and case.

• ο = masculine
• η = feminine
• το = neuter

So here, το is the correct form.

Παράσιτο is neuter.

A lot of Greek nouns ending in -ο are neuter, and παράσιτο follows that pattern. That is why it goes with το.

Its basic dictionary form is:

• το παράσιτο = the parasite

Είναι is the present-tense form of the verb to be.

In this sentence, it means is:

• Το παράσιτο είναι... = The parasite is...

A useful thing to know is that είναι is used for both:

• he/she/it is
• they are

So Greek learners often notice that the same form works for both singular and plural third person.

Στα is a contraction of:

• σε = in / on / at / to
• τα = the (neuter plural accusative)

So:

• σε τα → στα

In this sentence, στα φύλλα means on the leaves.

This is very common in Greek:

• στο = σε + το
• στη = σε + τη(ν)
• στον = σε + τον
• στα = σε + τα

Because Greek σε is broader than English in or on. It can mean in, on, at, or to, depending on context.

So στα φύλλα can naturally mean:

• on the leaves

The exact English preposition depends on the situation, but in Greek the same preposition σε is often used.

Φύλλα is the plural form of φύλλο.

• το φύλλο = the leaf
• τα φύλλα = the leaves

So the sentence is talking about more than one leaf.

If you wanted on the leaf singular, you would say:

• στο φύλλο

It is in the accusative plural.

That is because the preposition σε normally takes the accusative in Modern Greek. Since στα contains σε + τα, the noun after it appears in the accusative plural:

• τα φύλλα = nominative/accusative plural
• after σε → στα φύλλα

In this noun, the nominative and accusative plural happen to look the same, so you do not see a different ending here.

The given order is the most neutral, straightforward one:

• subject + verb + location

So:

• Το παράσιτο = subject
• είναι = verb
• στα φύλλα = location

Greek word order is more flexible than English, so other orders are possible for emphasis. For example, a speaker might move στα φύλλα earlier if they want to stress the location. But for a learner, the sentence as given is the most natural default pattern.

A simple pronunciation guide is:

• Το παράσιτο είναι στα φύλλα
• to pa-RA-si-to EE-ne sta FEE-la

A few notes:

• παράσιτο has the stress on ρά
• είναι has the stress on the first syllable
• φύλλα has the stress on φύ-
• υ in Modern Greek sounds like ee
• λλ is written double, but in normal Modern Greek pronunciation it is not pronounced like a long double consonant

Greek accent marks show which syllable is stressed.

So:

• παράσιτο → stress on ρά
• είναι → stress on the first syllable
• φύλλα → stress on φύ

Words like το and στα are one syllable, so they usually do not need an accent mark.

For learners, the accent marks are very important because they help you pronounce words correctly.

Yes, depending on context, παράσιτο can refer to a parasite in a biological sense or more generally a pest.

So if the context is gardening or plant disease, English might translate it as:

• The parasite is on the leaves
• The pest is on the leaves

The exact English choice depends on what kind of organism is being discussed.