The Italian determiner 'questo' means 'this' in English. It is used to indicate something that is close to the speaker or the person being addressed.
Meaning: this (referring to a singular masculine noun)
Questo libro è molto interessante.
This book is very interesting.
Meaning: this (referring to a singular feminine noun)
Questa penna scrive molto bene.
This pen writes very well.
Meaning: this (referring to a singular noun of unspecified gender)
Questo oggetto non mi appartiene.
This object does not belong to me.
Meaning: this (referring to a plural noun of any gender)
Questi quaderni sono tutti uguali.
These notebooks are all the same.
A1: Questo è il mio libro preferito.
This is my favorite book.
A1: Questo è un bel posto per fare una passeggiata.
This is a nice place for a walk.
A2: Questo vestito mi sta bene.
This dress fits me well.
B1: Ho comprato questo computer la settimana scorsa.
I bought this computer last week.
B1: Questo progetto richiederà molto tempo e impegno.
This project will require a lot of time and effort.
B2: Non capisco perché hai fatto questo.
I don't understand why you did this.
C1: Questo è il momento giusto per investire in azioni.
This is the right time to invest in stocks.
C1: Ho letto questo articolo interessante sul cambiamento climatico.
I read this interesting article about climate change.
C2: Questo sarebbe stato impossibile senza il tuo aiuto.
This would have been impossible without your help.
In Italian, 'questo' is a demonstrative determiner that is used to point out or refer to something that is nearby or within reach. It can be used with both singular and plural nouns, as well as masculine and feminine nouns. For example, 'questo libro' means 'this book', while 'questi libri' means 'these books'.
One important thing to note about 'questo' is that it agrees in gender and number with the noun it modifies. This means that if the noun is masculine singular, the determiner will be 'questo', but if the noun is feminine singular, the determiner will be 'questa'. Similarly, if the noun is masculine plural, the determiner will be 'questi', but if the noun is feminine plural, the determiner will be 'queste'.
Another use of 'questo' in Italian is as a pronoun, where it can stand alone to replace a previously mentioned noun. For example, if someone says 'Ho comprato un libro', meaning 'I bought a book', you could respond with 'Questo è molto interessante', which means 'This one is very interesting'. In this case, 'questo' is standing in for the previously mentioned book.