Learn Hardcore Italian: Trovo una sdraio rossa in giardino. - I find a red deckchair in the garden.

Trovo is the first-person singular present indicative of trovare, meaning “I find” or “I discover.” Here it indicates that you are finding or noticing the deckchair right now.

Why is sdraio feminine singular even though it ends in –o?

Italian has some irregular nouns that don’t follow the usual –o = masculine, –a = feminine pattern. Sdraio is one of these exceptions: it’s a feminine noun, so it takes feminine articles and adjectives (una, rossa), even though it ends in –o.

Why doesn’t sdraio change in the plural form?

Sdraio is invariable in the plural, meaning its form stays sdraio whether singular or plural. You mark the plural by using the plural article or numeral:

Singular: una sdraio (one deckchair)
Plural: due sdraio (two deckchairs)

Why is una used instead of un before sdraio?

Una is the feminine singular indefinite article. Since sdraio is feminine, you must use una. Un is reserved for masculine nouns.

Why does the adjective rossa come after sdraio, and why does it end in –a?

In Italian most descriptive adjectives follow the noun: sdraio rossa = red deckchair.
Rossa ends in –a to agree in gender (feminine) and number (singular) with sdraio.

Why is it in giardino instead of nel giardino or a giardino?

In giardino (without article) is the normal way to say “in the garden” when speaking generally.
Nel giardino (in + il) is also correct but more specific: “inside the (particular) garden.”
A giardino isn’t used because with places you enter or are enclosed in, Italian uses in, not a.

Could I use the passato prossimo and say Ho trovato una sdraio rossa in giardino?

Yes.

Ho trovato (I found) is the passato prossimo of trovare, used for past, completed actions.
Trovo (present) suggests you’re discovering it right now or making a general statement about finding it.

Does giardino always drop the article in this kind of sentence? What about its plural?

In expressions of location, you often omit the article:

in giardino = in the garden (generally)
In the plural you’d say nei giardini (in the gardens), since nei = in
- i (the plural masculine article).

Are there synonyms for sdraio, and do they work the same way?

A close synonym is lettino (especially by the pool or beach).

Lettino is masculine: un lettino rosso.
It follows regular –o/–i and –a/–e endings (un –i, una –e).