till
The word 'till' in Italian is 'fino'. It is used to indicate a point in time, a place, or a situation up to which something happens or is valid. For example, 'I'll be here till 5 o'clock' translates to 'Sarò qui fino alle cinque.'
I will work until five.
This sentence uses 'fino' to indicate a time limit or endpoint. It is here translated to 'until', meaning the action specified (work) will continue up to a certain time (five).
I will study deep into the night.
In this context, 'fino' is used to mean 'up to a point'. The phrase 'fino a notte fonda' means 'until late at night' or 'up to the deep night'. It's used to express prolonged activities.
I will walk until sunset.
Again, 'fino' here indicates a period up to which an activity will continue. 'al tramonto' means 'until sunset'. The action 'Camminerò' or 'I will walk' is set to continue till the point in time referred to as 'the sunset'.