Λερώνομαι εύκολα όταν μαγειρεύω.

Because it is a middle/passive-form verb. In this sentence, λερώνομαι does not mean a true passive like I am dirtied in a stiff English sense. It means I get dirty.

So:

• λερώνω = I dirty / I stain something
• λερώνομαι = I get dirty / I get stained

This is very common in Greek: a verb in -ομαι can sound passive in form, but in meaning it may be more like become, get, or be affected.

The difference is mainly about who is affected.

• λερώνω κάτι = I dirty something
• λερώνομαι = I get dirty

Examples:

• Λερώνω το πουκάμισο. = I dirty the shirt.
• Λερώνομαι εύκολα. = I get dirty easily.

So in your sentence, the speaker is not dirtying something else; the speaker is the one ending up dirty.

Because εύκολα is an adverb, and it modifies the verb λερώνομαι.

Here it means easily.

Compare:

• εύκολος / εύκολη / εύκολο = easy
  
  • adjective, used with nouns
• εύκολα = easily
  
  • adverb, used with verbs

So:

• ένα εύκολο φαγητό = an easy meal
• λερώνομαι εύκολα = I get dirty easily

A native English speaker often expects a separate word like easily, and that is exactly what εύκολα is doing here.

Because Greek usually does not need subject pronouns when the verb ending already shows who the subject is.

Here:

• λερώνομαι = I get dirty
• μαγειρεύω = I cook

The -μαι and -ω endings already tell you it is first person singular.

You can add εγώ if you want emphasis or contrast:

• Εγώ λερώνομαι εύκολα όταν μαγειρεύω.
  = I get dirty easily when I cook.

That sounds more emphatic, as if contrasting with someone else.

Because the sentence expresses a general habit or repeated situation.

• Λερώνομαι εύκολα = I get dirty easily
• όταν μαγειρεύω = when/whenever I cook

So the idea is not just about one single moment happening now. It means something like:

• Whenever I cook, I get dirty easily.

In Greek, the present tense is often used for habits, routines, and general truths, just like in English.

Here όταν means when or whenever.

In this sentence, because the verb after it is in the present tense (μαγειρεύω), it has a habitual sense:

• όταν μαγειρεύω = when I cook / whenever I cook

So the full sentence describes something that regularly happens.

This is a very common pattern in Greek:

• όταν + present for repeated or habitual situations

For example:

• Όταν διαβάζω, πίνω καφέ.
  = When/Whenever I study, I drink coffee.

Yes. Greek word order is more flexible than English word order.

Your sentence is natural:

• Λερώνομαι εύκολα όταν μαγειρεύω.

But you could also say:

• Όταν μαγειρεύω, λερώνομαι εύκολα.

That version puts more focus on the when I cook part first.

You can also move εύκολα around in some contexts, although the original placement is very normal and clear.

So the exact order is somewhat flexible, but the original sentence sounds completely natural.

Not necessarily. In both Greek and English, cook can be used without an object when the meaning is general.

So:

• Μαγειρεύω. = I cook / I do the cooking.

If you want to say what you cook, you can add it:

• Μαγειρεύω μακαρόνια. = I cook pasta.
• Μαγειρεύω το βραδινό. = I cook dinner.

But in your sentence, the exact food is not important. The point is just that during cooking, I get dirty easily.

In natural English, it is much more like I get dirty.

A very literal learner might think of myself, but Greek often uses these -ομαι forms where English prefers get + adjective/past participle or a simple intransitive verb.

So:

• natural English: I get dirty easily when I cook
• less natural: I dirty myself easily when I cook

The Greek sentence is ordinary and idiomatic; it does not sound strange or overly reflexive.

Μαγειρεύω is the first person singular present tense of μαγειρεύω = to cook.

So here it means:

• I cook

In this sentence, it is part of the clause introduced by όταν:

• όταν μαγειρεύω = when I cook / whenever I cook

So both main verbs in the sentence are first person singular present:

• λερώνομαι = I get dirty
• μαγειρεύω = I cook

That is why the sentence is very compact and does not need εγώ.