Πρόσεχε μην ανεβάσεις πολλή ταχύτητα όταν ο δρόμος είναι βρεγμένος.

Yes. Πρόσεχε is an imperative form of προσέχω (to pay attention / be careful).

In this sentence, Πρόσεχε means something like:

• Be careful
• Watch out
• Take care

A learner may notice that Greek often has two imperative styles here:

• Πρόσεχε = more continuous, like be careful / keep being careful
• Πρόσεξε = more punctual, like watch out / be careful

In real speech, both can be used, but Πρόσεχε can sound a bit more like ongoing caution.

Μην is used for negative commands or warnings.

So:

• ανεβάσεις by itself would not mean don’t increase
• μην ανεβάσεις = don’t increase

After words like Πρόσεχε, Greek often uses μην + verb to mean:

• be careful not to...
• make sure you don’t...

So:

• Πρόσεχε μην ανεβάσεις... = Be careful not to increase...

Because after μην in this kind of warning, Greek usually uses the subjunctive form, not the plain indicative.

Here:

• ανεβάζεις = you increase / you are increasing
• να ανεβάσεις / μην ανεβάσεις = subjunctive form, often used for actions that are intended, possible, or warned against

So:

• μην ανεβάζεις would usually mean don’t be increasing / don’t keep increasing
• μην ανεβάσεις means don’t increase / don’t go and increase

In this sentence, the speaker is warning against a possible action, so μην ανεβάσεις is the natural choice.

Literally, ανεβάζω means raise / increase, and ταχύτητα means speed.

So ανεβάζω ταχύτητα means:

• increase speed
• speed up

It is a normal Greek way to talk about driving faster.

So the sentence is warning the person not to speed up when the road is wet.

Because ταχύτητα is a feminine noun, and πολλή agrees with it.

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

• πολύς = masculine
• πολλή = feminine
• πολύ = neuter

Since η ταχύτητα is feminine, we get:

• πολλή ταχύτητα = a lot of speed / too much speed / high speed

This is a very common agreement pattern in Greek.

Yes, literally it means much / a lot of speed, and yes, it is natural Greek.

Greek often uses ανεβάζω πολλή ταχύτητα in contexts where English might prefer:

• go too fast
• build up too much speed
• speed up too much

So even if the wording is a bit different from English, it is idiomatic Greek.

Because όταν normally introduces a time clause meaning when, and here it refers to a general real situation.

• όταν ο δρόμος είναι βρεγμένος = when the road is wet

Greek commonly uses the indicative after όταν in statements like this.

This clause describes a real condition or recurring situation, not a command.

Ο δρόμος is in the nominative case because it is the subject of είναι.

Breaking it down:

• ο δρόμος = the road
• είναι = is
• βρεγμένος = wet

So literally:

• the road is wet

That makes ο δρόμος the subject, so nominative is exactly what we expect.

Because βρεγμένος agrees with ο δρόμος, which is masculine singular.

Agreement:

• βρεγμένος = masculine singular
• βρεγμένη = feminine singular
• βρεγμένο = neuter singular

Since δρόμος is masculine:

• ο βρεγμένος δρόμος = the wet road
• ο δρόμος είναι βρεγμένος = the road is wet

Greek adjectives and participle-like forms agree with the noun they describe.

Historically and grammatically, it is a passive participle form, but for learners it is often easiest to think of it as an adjective meaning wet.

It comes from the verb βρέχω (to wet / to make wet), and βρεγμένος means wetted / wet.

In everyday Greek, forms like this are very common and often behave just like adjectives:

• βρεγμένος δρόμος = wet road
• τα ρούχα είναι βρεγμένα = the clothes are wet

So both ideas are useful:

• grammar-wise: a participial form
• learner-wise: often basically an adjective

Because Greek does not need the article there.

The phrase is indefinite and general:

• πολλή ταχύτητα = a lot of speed / too much speed

If you added the article, it would sound more specific:

• την πολλή ταχύτητα = the high speed / the excessive speed

But in this warning, the speaker is talking generally about speed, so no article is needed.

Yes, that would also be possible, but it is slightly different in tone and wording.

• μην τρέχεις γρήγορα = don’t drive fast / don’t go fast
• μην ανεβάσεις πολλή ταχύτητα = don’t build up too much speed / don’t speed up too much

The original sentence focuses more on increasing speed, not just on being fast in general.

So the Greek sentence is a bit more specific than simply don’t drive fast.

It is informal singular, addressed to one person in the σύ form.

Clues:

• Πρόσεχε
• ανεβάσεις

If you wanted a plural or polite version, Greek would change the verb forms.

So this sentence is something you would say to:

• one friend
• one family member
• one driver you are addressing informally

Sometimes, but not always neatly.

In this sentence, μην does more than just mean not. It helps create a negative warning / negative command.

So rather than translating word for word, it is better to understand the whole chunk:

• Πρόσεχε μην ανεβάσεις... = Be careful not to increase...

That is more natural than treating μην as a simple standalone not.