Difference Between in and at
Although both ‘in’ and ‘at’ describe the location of a particular noun and appear to be alike but their use is different according English grammar.
‘In’ is a preposition that is used to indicate the location of someone at a particular time. As for example, ‘I was in the college when she came home’. Here I was in the college when she visited my home. The preposition ‘in’ gives us an idea well within a particular place.
The preposition ‘at’ is used to indicate the proximity of something. Let us cite an example ‘The car was at the office’. Here ‘at’ indicates the nearness of the car to the office. Unlike ‘in’, ‘at’ indicates the nearness to a particular place.