on
The Italian preposition su generally means 'on' or 'upon' in English.
preposition
Meaning: on
Il gatto è su il tavolo.
The cat is on the table.
Meaning: about
Stiamo discutendo su la questione.
We are discussing about the issue.
Meaning: up
Ho bisogno di alzarmi su presto domani mattina.
I need to get up early tomorrow morning.
Meaning: over
Metti il coperchio su la pentola.
Put the lid over the pot.
Meaning: upon
Su mia madre giuro che non ho fatto niente di male.
Upon my mother, I swear I did nothing wrong.
A1: Il libro è su tavolo.
The book is on the table.
A1: Ho messo il cappotto su sedia.
I put my coat on the chair.
A2: La foto è appesa su muro.
The photo is hanging on the wall.
B1: Siamo andati su una montagna alta.
We went to a high mountain.
B1: Ho scritto un messaggio su WhatsApp ieri sera.
I wrote a message on WhatsApp last night.
B2: Ho studiato molto su questo argomento.
I have studied a lot about this topic.
B2: Suonavo la chitarra quando mio amico mi ha chiamato.
I was playing guitar when my friend called me.
C1: Su di lui gravitano molte voci.
Many rumors revolve around him.
C1: L'azienda si concentra su innovazione tecnologica.
The company focuses on technological innovation.
C2: Su questo argomento si sono scritti molti libri.
Many books have been written on this topic.
Su is a very common preposition in Italian and has a wide range of uses. Its primary meaning is 'on' or 'upon', as in 'il libro è su tavolo' (the book is on the table). It can also be used to indicate location, as in 'vivo su via Roma' (I live on Via Roma). In some cases, it can even be translated as 'about' or 'concerning', such as in the phrase 'un libro su Dante' (a book about Dante).
In addition to its basic meanings, su can also be used in a number of idiomatic expressions. For example, 'su due piedi' literally means 'on two feet', but is used to mean 'immediately' or 'right away'. Similarly, 'su tutti i fronti' means 'on all fronts' and is used to describe someone who is involved in many different activities or projects at once.
One thing to keep in mind when using su is that it often requires specific articles or pronouns to be used with it. For example, you would say 'sono su una sedia' (I am on a chair), but you would say 'sono sulla sedia' (I am on the chair) if you were referring to a specific chair. Likewise, you would say 'scrivi su di me' (write on me), but you would say 'scrivi sul mio braccio' (write on my arm) if you were referring to a specific body part.