Με αυτό το μικρό εργαλείο μπορώ να ξεβιδώνω τη βίδα όταν θέλω να καθαρίσω το ράφι.

Με means with, and here it shows the instrument used to do the action: with this small tool.

So:

• με = with
• με αυτό το μικρό εργαλείο = with this small tool

This is a very common Greek pattern for saying what you use to do something:

• γράφω με μολύβι = I write with a pencil
• κόβω με μαχαίρι = I cut with a knife

After με, Greek normally uses the accusative.

In Greek, demonstratives like αυτός, αυτή, αυτό normally appear together with the definite article when they come before a noun.

So Greek says:

• αυτό το εργαλείο = this tool

not usually just:

• αυτό εργαλείο

This is normal Greek structure:

• αυτό το βιβλίο = this book
• αυτή η πόρτα = this door
• αυτό το σπίτι = this house

So αυτό is the demonstrative (this) and το is the article (the), and Greek commonly uses both.

Because εργαλείο is a neuter singular noun, and the adjective has to agree with it in gender, number, and case.

So:

• εργαλείο = neuter singular
• μικρό = neuter singular form of μικρός = small

Compare:

• μικρός άντρας = small man
• μικρή τσάντα = small bag
• μικρό εργαλείο = small tool

Greek adjectives must match the noun they describe.

It is in the accusative singular, because it follows με.

However, with many neuter nouns, the nominative and accusative forms are the same, so εργαλείο looks unchanged.

For example:

• nominative: το εργαλείο
• accusative: το εργαλείο

So even though it looks the same, its function in the sentence is accusative because of με.

This is about aspect, which is very important in Greek.

• ξεβιδώνω = imperfective
• ξεβιδώσω = perfective subjunctive form after να

With μπορώ να, both aspects can be possible, but they give a different feeling:

• μπορώ να ξεβιδώνω suggests a general ability, something I can do whenever needed, or possibly repeatedly
• μπορώ να ξεβιδώσω would sound more like I can unscrew it / manage to unscrew it in a more single, complete-event sense

In this sentence, ξεβιδώνω fits the idea of a repeated or general-use situation:

With this small tool, I can unscrew the screw whenever I want to clean the shelf.

So the imperfective works well because it describes a useful ability in general, not just one isolated success.

The prefix ξε- often gives the sense of:

• undoing
• removing
• reversing
• off / un-

So:

• βιδώνω = I screw in / fasten with a screw
• ξεβιδώνω = I unscrew / remove by unscrewing

This prefix is very common in Greek. A few examples:

• δένω = tie

• ξεδένω = untie

• κλειδώνω = lock
• ξεκλειδώνω = unlock

So ξεβιδώνω is basically un-screw.

Because βίδα is the direct object of ξεβιδώνω.

You unscrew the screw, so the screw is what receives the action.

• η βίδα = the screw (nominative)
• τη βίδα = the screw (accusative)

Since βίδα is feminine singular, the accusative article is τη(ν).

That is why Greek says:

• ξεβιδώνω τη βίδα = I unscrew the screw

Both are related forms of the same article:

• full form: την
• shortened form before many consonants: τη

Before a consonant like β, Greek often drops the final -ν in everyday spelling and speech:

• τη βίδα
• τη μάνα
• τη φίλη

But before vowels or certain consonants, the -ν is often kept:

• την άκρη
• την κόρη
• την πόρτα (many speakers keep it here too)

Modern usage varies a bit, and spelling conventions are not always identical everywhere, but τη βίδα is completely normal.

Όταν means when / whenever.

So:

• όταν θέλω = when(ever) I want

In this sentence, it means that whenever the speaker wants to clean the shelf, they are able to unscrew the screw using that tool.

This gives a repeated or general-time meaning, not just one specific moment.

Again, this is an aspect question.

• καθαρίσω = perfective
• καθαρίζω = imperfective

After θέλω να, the perfective often means to do the action as a complete event:

• θέλω να καθαρίσω το ράφι = I want to clean the shelf

This focuses on the cleaning as one complete task.

If you said:

• θέλω να καθαρίζω το ράφι

it would sound more like:

• I want to be cleaning the shelf
• I want to clean the shelf regularly / as an ongoing activity

So να καθαρίσω is the natural choice here because the speaker means a single cleaning action each time.

Because Greek can stack these verb structures naturally.

The sentence contains:

• μπορώ να ξεβιδώνω = I can unscrew
• όταν θέλω να καθαρίσω = when I want to clean

So there are really two separate verb phrases:

1. μπορώ να ξεβιδώνω τη βίδα
2. θέλω να καθαρίσω το ράφι

Each verb chooses the aspect that best fits its own meaning:

• μπορώ να ξεβιδώνω = general ability
• θέλω να καθαρίσω = desire to complete a cleaning action

So the different forms are not contradictory; they reflect different meanings.

Greek uses the definite article very often, especially when the thing is specific or understood from context.

Here, το ράφι means the shelf, probably a particular shelf the speaker has in mind.

So:

• καθαρίσω το ράφι = clean the shelf

Greek often uses the article in places where English might sound more flexible. If it is a known, specific object, Greek strongly prefers the definite article.

Because Greek is a pro-drop language, which means the subject pronoun is often omitted when the verb ending already shows who the subject is.

Here:

• μπορώ already means I can

So Greek does not need εγώ unless there is emphasis or contrast.

Compare:

• μπορώ να ξεβιδώνω = I can unscrew
• εγώ μπορώ να ξεβιδώνω = I can unscrew / I can unscrew

The second version sounds more emphatic.

Yes. Greek word order is more flexible than English word order, because case endings and verb forms already show a lot of the grammatical relationships.

The original sentence is perfectly natural:

• Με αυτό το μικρό εργαλείο μπορώ να ξεβιδώνω τη βίδα όταν θέλω να καθαρίσω το ράφι.

But Greek could also move parts around for emphasis, for example:

• Μπορώ να ξεβιδώνω τη βίδα με αυτό το μικρό εργαλείο όταν θέλω να καθαρίσω το ράφι.
• Όταν θέλω να καθαρίσω το ράφι, μπορώ να ξεβιδώνω τη βίδα με αυτό το μικρό εργαλείο.

These versions all mean roughly the same thing, but the emphasis changes slightly depending on what comes first.

Yes, it is normal Greek.

Even though unscrew the screw sounds slightly repetitive in English, Greek commonly uses ξεβιδώνω τη βίδα to say exactly what is being removed or loosened.

Greek is often perfectly happy to use a verb and its related object together if the meaning is clear and natural.

So this is not strange Greek; it is a straightforward way to say that the screw is what gets unscrewed.

Here are the main forms you would normally look up:

• με = with
• αυτός, αυτή, αυτό = this
• μικρός, μικρή, μικρό = small
• εργαλείο = tool
• μπορώ = can, be able
• ξεβιδώνω = unscrew
• βίδα = screw
• όταν = when
• θέλω = want
• καθαρίζω = clean
• ράφι = shelf

Notice that some verbs appear in the sentence in one form, but the dictionary may list a different basic form. For example:

• sentence: καθαρίσω
• dictionary form: καθαρίζω

That is because καθαρίσω is part of the perfective/subjunctive system, while καθαρίζω is the usual dictionary form.

Greek spelling marks stress with an accent, so the written sentence already tells you where to stress each word:

• αυτό
• μικρό
• εργαλείο
• μπορώ
• ξεβιδώνω
• βίδα
• όταν
• θέλω
• καθαρίσω
• ράφι

That accent mark is very important in Greek. It is not optional, and it helps you pronounce the word correctly.

For example:

• εργαλείο is stressed on the last -εί-
• ξεβιδώνω is stressed on -νώ
• καθαρίσω is stressed on -ρί-

So Greek is actually quite helpful here: the spelling shows the stress directly.