Il tarlo rovina il legno massello.

Because both nouns are masculine singular.

• il tarlo = the woodworm
• il legno massello = the solid wood

In Italian, the definite article usually agrees with the noun in gender and number. Here:

• tarlo is masculine singular, so it takes il
• legno is masculine singular, so it also takes il

Also, Italian often uses the definite article where English might not, especially when talking about things in a general sense.

Tarlo usually refers to a wood-boring insect or woodworm. In everyday Italian, it often suggests the kind of pest that damages wood from the inside.

It can also be used figuratively in Italian to mean an obsession, nagging doubt, or something that eats away at you mentally, but in this sentence it is clearly the literal insect.

Because rovina is the conjugated form of the verb rovinare.

The infinitive is rovinare = to ruin / to damage.

Here, the subject is il tarlo, which is third person singular, so the verb becomes:

• io rovino = I damage
• tu rovini = you damage
• lui/lei rovina = he/she/it damages

So:

• Il tarlo rovina... = The woodworm damages...

In this sentence, the most natural reading is based on normal Italian word order:

subject + verb + object

So:

• Il tarlo = subject
• rovina = verb
• il legno massello = direct object

Even though both nouns are masculine singular and both use il, Italian normally places the subject before the verb and the object after it in a simple statement like this.

Legno massello means solid wood, meaning wood that is solid throughout, not plywood, chipboard, veneer, or other engineered material.

So this phrase refers to a type of material.

In this expression:

• legno = wood
• massello adds the idea of solid / made of solid wood

It is a common fixed expression in Italian.

Because in Italian, adjectives usually come after the noun, and many set expressions follow that pattern.

So:

• legno massello = solid wood

This sounds natural in Italian. Putting massello before legno would sound wrong here.

Also, this is a fairly standard expression, so it is best learned as a chunk: legno massello.

Functionally, yes: it describes legno.

However, learners sometimes notice that massello can also exist as a noun in other contexts. In legno massello, though, you can think of it as part of a fixed expression meaning solid wood.

The important practical point is:

• treat legno massello as the normal Italian way to say solid wood

Yes, depending on context.

Rovinare can mean:

• to ruin
• to spoil
• to damage

In this sentence, damages is often the most natural English choice, because a woodworm typically harms wood gradually. But ruins is not impossible if the damage is severe.

So the verb has a broad meaning, and the best English translation depends on tone and context.

Because Italian uses the definite article more often than English.

For example, English might say:

• Woodworm damages solid wood
• The woodworm damages solid wood

Italian usually prefers the article in a sentence like this:

• Il tarlo rovina il legno massello.

This can refer to:

• a specific woodworm and a specific piece/type of solid wood, or
• a general truth stated with singular nouns

Italian often uses the definite article for general statements in a way that feels more natural than leaving it out.

Yes, but the basic order here is the most neutral and natural:

Il tarlo rovina il legno massello.

Italian word order is more flexible than English, but changing it can affect emphasis or style. For example, moving il legno massello to the front would sound more marked and less neutral.

For a learner, the safest pattern is:

subject + verb + object

The plurals are:

• il tarlo → i tarli
• il legno → usually i legni, but that often means types of wood
• il legno massello → i legni masselli is grammatically possible, but in real usage people often rephrase depending on context

A useful point: legno is often treated as a material noun, so singular is very common when talking about wood as a substance.

A simple pronunciation guide is:

eel TAR-lo ro-VEE-na eel LEH-nyo mas-SEL-lo

A few notes:

• il sounds roughly like eel
• tarlo has a clear r
• rovina stresses vi
• legno has gn, which sounds like the ny in canyon
• massello stresses sel

So legno is not pronounced like leg-no in English; it is closer to LEH-nyo.

It can do either, depending on context.

Without extra context, Italian allows this sentence to be understood as:

• a specific situation: The woodworm is damaging the solid wood
• a general statement: The woodworm damages solid wood

This is one reason definite articles can be tricky for English speakers: Italian often uses them both for specific reference and for general truths.