Prepositions of movement

At and in

At and in can also be used as prepositions of movement, but they're used to show the purpose of the movement.

For example:

I threw the paper in the bin.

 Let's have dinner at my place.

When used after some verbs, the preposition at also shows the target of an action:

 The bowler was sent off for throwing the ball at the umpire, instead of to the batsman.

!Note - a lot of sites say that around and round are the same, but there can be a difference, especially in BrE. If someone says "they were running around", it implies the movement is erratic.

For example: Children tend to run around at school.

 In BrE when we use "round" we imply a more definite purpose and a more circular movement.

For example: The athlete ran round the track.