La ghiaia copre il sentiero.

Italian uses definite articles more often than English does. In a simple sentence like this, la ghiaia sounds natural, even if English might just say gravel with no article.

So:

• la ghiaia = the gravel
• but in English, the is often omitted where Italian keeps it

Using bare ghiaia here would sound unnatural in standard Italian.

It is grammatically singular and feminine.

Even though gravel is made up of many small stones, Italian treats ghiaia as a mass noun, like sand or water in English. Because it is singular, the verb is singular too:

• la ghiaia copre
• not la ghiaia coprono

A plural form ghiaie does exist, but it is usually used in technical or specialized contexts to mean different kinds or deposits of gravel.

Because the subject is la ghiaia, which is singular.

Italian verbs must agree with the subject in person and number. Since ghiaia is a singular noun, the verb must also be singular:

• la ghiaia copre = singular subject + singular verb

If the subject were plural, then you would use coprono:

• Le pietre coprono il sentiero.

Copre is the third-person singular present indicative of coprire, meaning to cover.

Present tense of coprire:

• io copro
• tu copri
• lui/lei copre
• noi copriamo
• voi coprite
• loro coprono

Here, copre matches la ghiaia.

It can mean either one, depending on context.

Italian present tense often covers both:

• covers
• is covering

So La ghiaia copre il sentiero could mean:

• The gravel covers the path
• The gravel is covering the path

If you want to strongly emphasize an ongoing action, Italian often uses stare + gerund:

• La ghiaia sta coprendo il sentiero.

Because sentiero is a masculine singular noun that begins with a normal consonant sound, so it takes il.

Use lo with masculine singular nouns beginning with:

• s + consonant: lo studente
• z: lo zaino
• ps: lo psicologo
• gn: lo gnomo
• x, y, and a few others

But sentiero begins with just s followed by a vowel, so it takes il:

• il sentiero

Ghiaia is pronounced roughly GYA-ya.

A more careful breakdown:

• ghi = a hard g sound, like g in get, not like g in giant
• then aia sounds like a-ya

So:

• ghiaia ≈ GYA-ya

The h is not pronounced by itself. Its job is to keep the g hard before i.

In a neutral Italian sentence, the usual word order is:

subject + verb + object

So in:

• La ghiaia copre il sentiero

the most natural reading is:

• la ghiaia = subject
• copre = verb
• il sentiero = object

In other words, the gravel is doing the covering, and the path is what gets covered.

Italian can change word order for emphasis, but this sentence is straightforward standard SVO order.

Yes. A very common alternative is the passive:

• Il sentiero è coperto dalla ghiaia.

That means The path is covered by the gravel.

The difference is mostly one of focus:

• La ghiaia copre il sentiero focuses on the gravel doing the action
• Il sentiero è coperto dalla ghiaia focuses on the path and its condition

Both are correct.

• ghiaia is feminine singular
• sentiero is masculine singular

That is why the articles are:

• la ghiaia
• il sentiero

Their usual plurals are:

• le ghiaie (less common in everyday speech)
• i sentieri