Il profumo dell’arrosto riempie la cucina.

Dell’arrosto means of the roast.

It is made from:

• di = of
• il = the

Normally, di + il = del. But before a word beginning with a vowel, Italian uses dell’:

• di + l’ / dello-type form before a vowel → dell’
• arrosto begins with a, so you get dell’arrosto

So:

• il profumo dell’arrosto = the smell/aroma of the roast

Italian uses definite articles more often than English does.

Here:

• il profumo = the aroma/smell
• la cucina = the kitchen

In English, you might sometimes say Roast smell fills the kitchen in a poetic way, but Italian normally wants the articles:

• Il profumo dell’arrosto riempie la cucina.

This sounds natural and standard.

Here, arrosto is a noun.

So l’arrosto means the roast or the roast meat / roast dish.

Italian also has related uses where arrosto can feel adjective-like in other contexts, but in this sentence it is best understood as a noun:

• il profumo dell’arrosto = the aroma of the roast

Riempie is the third-person singular present of riempire = to fill.

The subject is:

• Il profumo dell’arrosto = the aroma of the roast

That subject is singular, so the verb must also be singular:

• il profumo ... riempie

A quick pattern:

• io riempio = I fill
• tu riempi = you fill
• lui/lei riempie = he/she/it fills

So riempie means fills.

The subject is:

• Il profumo dell’arrosto

That whole noun phrase means the aroma of the roast.

The verb is:

• riempie = fills

The direct object is:

• la cucina = the kitchen

So the structure is:

• [Subject] Il profumo dell’arrosto
• [Verb] riempie
• [Object] la cucina

Italian usually does not need subject pronouns when the verb already shows the person and number.

So instead of saying something like It fills the kitchen, Italian simply says:

• Il profumo dell’arrosto riempie la cucina.

Adding a pronoun such as esso would sound unnatural in normal speech. Italian normally uses the noun itself, or just the verb if the subject is already understood.

No. Profumo can mean:

• perfume in some contexts
• fragrance
• pleasant smell
• aroma

With food, profumo often means aroma or delicious smell.

So in this sentence, profumo is not talking about bottled perfume. It means the pleasant smell coming from the roast.

The normal, neutral word order is:

• Il profumo dell’arrosto riempie la cucina.

That is a standard subject + verb + object pattern.

Italian word order is somewhat flexible, so other versions are possible for emphasis, but they are more marked. For example:

• La cucina è riempita dal profumo dell’arrosto. = The kitchen is filled by the aroma of the roast.

That changes the focus and style. The original sentence is the most natural straightforward version.

It is the present indicative.

So the sentence is describing what is happening now, or presenting it as a vivid current scene:

• riempie = fills / is filling

In Italian, the present tense is very common for descriptions like this.

A simple guide is:

• dell’arrosto ≈ del-lar-ROS-to

A few useful points:

• The apostrophe shows that the article contracts before a vowel.
• The rr in arrosto is a rolled or tapped r, stronger than in English.
• Stress falls on ROS: ar-ROS-to

So the full sentence is roughly:

• Il profumo dell’arrosto riempie la cucina
• ≈ eel pro-FOO-mo del-lar-ROS-to ree-EM-pyeh la koo-CHEE-na

No. In standard Italian, del arrosto is not correct here.

Before a vowel, you use the contracted form with apostrophe:

• dell’arrosto

So:

• di + il → del
• but before a vowel sound, the correct form here is dell’

That is why the sentence uses:

• il profumo dell’arrosto
  not
• il profumo del arrosto