Modello l'argilla con le mani.

Because Italian often drops the subject pronoun when it is clear from the verb ending.

Here, modello ends in -o, which tells you the subject is I. So:

• Modello l'argilla con le mani. = I model the clay with my hands.

You could say Io modello l'argilla con le mani, but io would usually add emphasis, contrast, or clarity.

Modello is the 1st person singular present indicative of modellare.

So it means:

• I model
• I shape
• I mold

Depending on context, the Italian present tense can also correspond to English I am modeling / shaping / molding.

Be aware that modello can also be a noun in other contexts, meaning model, but in this sentence it is clearly a verb.

Because argilla begins with a vowel, and la becomes l' before a vowel. This is called elision.

So:

• la + argilla → l'argilla

Also, argilla is a feminine singular noun, which is why the article is la / l' rather than il / lo / l'.

Italian uses articles more often than English.

So l'argilla can mean:

• the clay in a specific situation
• sometimes clay more generally, depending on context

English often leaves the article out where Italian prefers to include it. That is very normal.

In Italian, when talking about body parts, the definite article is very common, especially when it is obvious whose body parts they are.

So:

• con le mani = with the hands, but naturally understood as with my hands here

Italian often says:

• Mi lavo le mani. = I wash my hands.
• Scrivo con la mano destra. = I write with my right hand.

So con le mani is the normal, natural phrasing.

Yes, and mano is an important irregular noun.

Even though it ends in -o, it is feminine:

• la mano = the hand
• le mani = the hands

So in the sentence:

• con le mani is correct

Not con i mani.

Because the sentence suggests the action is being done with both hands, which is the most natural interpretation.

If you wanted to say with one hand, you would say:

• con la mano

But con le mani is the usual choice for shaping clay.

Yes. Con le mie mani is grammatically correct, but it adds more emphasis.

Compare:

• con le mani = the normal, neutral way
• con le mie mani = with my hands / with my own hands, more explicit or emphatic

In many everyday sentences, Italian prefers the article alone when possession is obvious.

Yes. Italian word order is more flexible than English, although some orders sound more neutral than others.

The original sentence is a very natural neutral order:

• Modello l'argilla con le mani.

You could also say:

• Con le mani modello l'argilla.

This puts more focus on how the action is done.

So the original order is standard, but other orders are possible for emphasis.

It can mean either, depending on context.

Italian present tense often covers both:

• I model clay
• I am modeling clay

If you want to stress that the action is happening right now, Italian can also use:

• Sto modellando l'argilla con le mani.

That is closer to I am modeling the clay with my hands.

A simple approximation is:

• mo-DEL-lo lar-JIL-la kon le MA-ni

A few useful notes:

• modello has stress on del
• argilla has stress on gil
• the g in argilla sounds like the j in jam
• double consonants in Italian, like ll, are pronounced more strongly than in English

So try to say it smoothly as:

modello l'argilla con le mani