Η φίλη μου λέει ότι το γρασίδι στην αυλή θέλει νερό κάθε βράδυ.

In Greek, common nouns usually take the definite article much more often than in English. So η φίλη μου is the normal way to say my friend.

• η = the, feminine singular
• φίλη = friend, feminine singular
• μου = my

You can sometimes hear φίλη μου without the article, but that is usually in special contexts, such as direct address or a more stylistically marked phrase. In a neutral sentence, η φίλη μου is the standard choice.

Because Greek weak possessive forms normally come after the noun:

• η φίλη μου = my friend
• το σπίτι μου = my house
• ο αδερφός μου = my brother

So μου here is not to me. It is the possessive form meaning my.

This can confuse English speakers because Greek μου can also mean to me, but in this sentence it clearly belongs to φίλη.

It is the genitive form of the pronoun εγώ.

Greek uses these weak genitive pronouns for possession:

• μου = my
• σου = your
• του / της / του = his / her / its
• μας = our
• σας = your
• τους = their

So grammatically, η φίλη μου is literally something like the friend of me, even though in natural English we say my friend.

λέει is the 3rd person singular present of λέω = to say / to tell.

So:

• λέω = I say
• λες = you say
• λέει = he/she/it says

Here the subject is η φίλη μου, so λέει means she says.

ότι introduces a clause and means that:

• Η φίλη μου λέει ότι... = My friend says that...

It connects the main clause to what is being said.

In everyday Greek, you may also hear πως used in the same way:

• λέει ότι...
• λέει πως...

Both can mean says that...

Yes. γρασίδι is a neuter noun, so it takes the neuter article το:

• το γρασίδι = the grass

Greek nouns have grammatical gender, and the article must agree with the noun:

• masculine: ο
• feminine: η
• neuter: το

English speakers often want to connect gender to natural sex, but in Greek grammatical gender is just part of the noun’s form. Since γρασίδι is neuter, you must say το γρασίδι.

στην is the contraction of σε + την.

• σε = in / at / on / to
• την = the, feminine accusative singular
• στην = in the / at the / to the

So:

• στην αυλή = in the yard / in the courtyard

Greek very commonly contracts σε with the definite article:

• σε + το = στο
• σε + τη(ν) = στη / στην
• σε + τον = στον

Because the preposition σε normally takes the accusative case.

The noun αυλή is feminine singular, and after σε you get:

• στην αυλή

In this particular noun, the nominative and accusative singular look the same in the noun itself:

• nominative: η αυλή
• accusative: την αυλή

So the change is visible mainly in the article.

Yes, θέλει literally comes from want, but in everyday Greek it is very often used where English would say need.

So:

• Το γρασίδι θέλει νερό. = The grass needs water.
• Το αυτοκίνητο θέλει βενζίνη. = The car needs petrol/gas.
• Το φαγητό θέλει αλάτι. = The food needs salt.

This is a very common and natural Greek pattern. So in this sentence, θέλει νερό is best understood as needs water, not as a human-like wants water.

Because νερό is being used as a mass noun in a general sense.

• θέλει νερό = needs water

This is similar to English, where we also usually say needs water, not needs the water.

If you added the article, το νερό, it would usually sound more specific, as if you meant a particular water already known from context.

Because κάθε means every / each and normally goes directly before the singular noun, without an article:

• κάθε μέρα = every day
• κάθε νύχτα = every night
• κάθε βράδυ = every evening / every night

So κάθε βράδυ is the normal structure.

No. In Greek, many time expressions appear without a preposition, especially when giving frequency or repeated time.

So:

• κάθε βράδυ = every night
• κάθε μέρα = every day
• κάθε χρόνο = every year

This is completely normal Greek usage.

Not completely. Greek word order is more flexible than English because articles and endings help show how words relate to each other.

The sentence as given is a natural neutral order:

• Η φίλη μου λέει ότι το γρασίδι στην αυλή θέλει νερό κάθε βράδυ.

But other orders are also possible, depending on emphasis. For example:

• Η φίλη μου λέει ότι κάθε βράδυ το γρασίδι στην αυλή θέλει νερό.
• Το γρασίδι στην αυλή θέλει νερό κάθε βράδυ, λέει η φίλη μου.

These do not all feel exactly the same in emphasis, but they are grammatically possible.

Sometimes in informal speech Greek can omit ότι after verbs like λέω, especially when the meaning is clear. But in a standard learner sentence like this, keeping ότι is the safest and most natural choice.

So for learners, it is best to think:

• λέει ότι... = says that...

That will keep your sentences clear and correct.