around
The German word 'um' is a preposition that is used to express the concept of 'around' in a spatial or temporal sense. It can be used to indicate the location of something in relation to something else, as in 'The park is around the corner'. It can also be used to indicate the time when something happens, as in 'I'll be back around 5 o'clock'.
I am going around the park.
In this sentence, 'um' is used as a preposition to indicate a movement around a certain location, in this case around the park.
It is half past five.
In this example, the term 'um' is used to specify the time. The phrase 'um halb sechs' literally translates to 'at half to six', which is the German way of expressing 'half past five'.
I am doing this to help you.
In this sentence, 'um' is used as a conjunction that introduces an infinitive clause. 'Um dich zu helfen' translates as 'in order to help you' or 'to help you'.