Φαρδαίνω το πουκάμισο.

Because -ω is the usual ending for the 1st person singular present in Modern Greek. So Φαρδαίνω means I widen / I am widening / I make wider.

In this sentence, Greek does not need a separate word for I. The verb ending already shows the subject.

Greek often leaves out subject pronouns when they are already clear from the verb.

So:

• Φαρδαίνω το πουκάμισο. = I widen / I am widening the shirt.

If you want extra emphasis, you could say:

• Εγώ φαρδαίνω το πουκάμισο. = I am widening the shirt.

But in normal speech, εγώ is usually unnecessary.

It means to make something wider.

So Φαρδαίνω το πουκάμισο means something like:

• I widen the shirt
• I am making the shirt wider
• I let the shirt out (depending on context, especially clothing)

It comes from φαρδύς / φαρδύ, meaning wide.

Το is the definite article, meaning the.

So:

• πουκάμισο = shirt
• το πουκάμισο = the shirt

Greek uses articles very regularly, often more regularly than English does. If you are talking about a specific shirt, το is natural and expected.

Πουκάμισο is a neuter noun.

That is why it takes the neuter singular article το:

• το πουκάμισο = the shirt

In Greek, every noun has grammatical gender, and the article has to match it.

It is in the accusative, but for this noun, the nominative and accusative singular look the same.

So:

• nominative: το πουκάμισο
• accusative: το πουκάμισο

Since Φαρδαίνω is a transitive verb, the shirt is the direct object, so it is in the accusative. It just happens that the form does not visibly change here.

Yes. It is present tense, and in Greek the present can often cover both:

• I widen the shirt
• I am widening the shirt

The exact English translation depends on context.

For example, if someone asks what you are doing right now, this could mean:

• I’m widening the shirt.

If you are talking more generally about what you do, it could mean:

• I widen the shirt.

A rough pronunciation is:

• far-THE-no

More carefully:

• φαρ- sounds like far
• -δαί- has the stress, roughly like THENE / THE
• -νω sounds like no

A few useful points:

• φ sounds like English f
• δ in Modern Greek sounds like th in this, not like English d
• αι here sounds like e

So Φαρδαίνω is approximately far-THE-no.

Yes. In Modern Greek, verbs are normally listed in dictionaries in the 1st person singular present, not in an infinitive form.

So the dictionary form is:

• φαρδαίνω

That can feel unusual to English speakers, because English dictionaries use to widen, but Greek dictionaries usually give the form meaning I widen.

Yes. Greek can also express the idea with a structure like:

• Κάνω το πουκάμισο πιο φαρδύ.
  = I make the shirt wider.

But Φαρδαίνω το πουκάμισο is a direct, natural verb-based way to say it.

So for a learner, it is useful to see that Greek can express this idea either:

• with a single verb: φαρδαίνω
• or with κάνω ... πιο φαρδύ = make ... wider

Usually, yes, it most naturally refers to making something physically broader or wider.

In this sentence, with το πουκάμισο, the meaning is clearly physical: you are altering the shirt so it is wider.

So the sentence is easy to understand as a practical, concrete action, especially in a sewing or tailoring context.