Καλύτερα να ρωτήσεις τον ναυαγοσώστη παρά να κάνεις βουτιά εκεί που δεν ξέρεις αν τα νερά είναι ρηχά ή βαθιά.

Καλύτερα means better. In Greek, Καλύτερα να + verb is a very common way to give advice, like It’s better to... or You’d better... in English.

Greek often leaves out είναι in this kind of expression, so Καλύτερα να ρωτήσεις... is a natural shortened form of Είναι καλύτερα να ρωτήσεις...

Modern Greek usually does not use an infinitive the way English does. Instead, it uses να plus a verb form.

So where English says to ask or to dive, Greek says να ρωτήσεις and να κάνεις βουτιά. In this sentence, να is part of the structure that follows Καλύτερα and introduces the action being recommended.

Ρωτήσεις is the 2nd person singular aorist subjunctive form of ρωτάω / ρωτώ, used here after να.

That sounds technical, but the main idea is simple: it refers to a single, complete action, ask. So να ρωτήσεις means to ask / that you ask, with the sense of one act of asking.

A useful comparison:

• να ρωτήσεις = ask, once / as a complete action
• να ρωτάς = be asking / ask repeatedly or habitually

Because ναυαγοσώστη is the direct object of ρωτήσεις. You are asking the lifeguard, so Greek uses the accusative case.

That is why both the article and the noun change:

• nominative: ο ναυαγοσώστης
• accusative: τον ναυαγοσώστη

Here παρά means rather than or than.

The pattern is: Καλύτερα να X παρά να Y
= Better to X than to Y

So: Καλύτερα να ρωτήσεις τον ναυαγοσώστη παρά να κάνεις βουτιά...
means It’s better to ask the lifeguard than to dive...

Greek often uses κάνω + noun where English uses a single verb.
So κάνω βουτιά literally means do a dive, but naturally it means take a dive or dive.

This is a very normal Greek expression. You could also hear να βουτήξεις, but να κάνεις βουτιά is idiomatic and common.

Also, the sentence does not use μια before βουτιά, because it is speaking generally. If you said να κάνεις μια βουτιά, that would sound a bit more like take a dive once / take a specific dive.

Εκεί means there, and που here means where. Together, εκεί που means where, in the place where, or more literally there where.

So: εκεί που δεν ξέρεις...
means
where you don’t know...

This is a very common Greek structure.

Greek often leaves out subject pronouns because the verb ending already shows who the subject is. This is called a pro-drop language.

In this sentence:

• ρωτήσεις = you ask
• κάνεις = you do
• ξέρεις = you know

So Greek does not need εσύ unless it wants extra emphasis or contrast.

Αν can mean if or whether, depending on context.

Here it introduces an indirect yes/no question: δεν ξέρεις αν τα νερά είναι ρηχά ή βαθιά
= you don’t know whether the waters are shallow or deep

So this is not really a conditional if. It is the same idea as English whether.

In Greek, τα νερά is very natural when talking about the waters of a place, water conditions, or a stretch of sea, river, etc.

So τα νερά here means something like the waters there or the water in that area. English can do something similar with the waters, especially in warnings or descriptions.

Greek often prefers the plural in this kind of context.

Because they agree with τα νερά.

Νερά is:

• neuter
• plural

So the adjectives also have to be neuter plural:

• ρηχά = shallow
• βαθιά = deep

That is why Greek does not use forms like ρηχό or βαθύ here. Those would be singular and would not match τα νερά.

Because ή means or, and Greek writes it with an accent mark to distinguish it from η, which is the feminine article the.

So:

• ή = or
• η = the for feminine nouns

This is a very useful distinction to notice when reading.

Not exactly. It is advice or a recommendation, not a direct order.

It can sound fairly strong in context, especially in a warning like this one, but grammatically it is softer than an imperative. It is closer to:

• You’d better ask the lifeguard
• It would be better to ask the lifeguard

So the tone is cautionary rather than purely commanding.