Fill in the blank with a suitable preposition:
I waited _______ the bus stop for ten minutes.
a. At
b. In
c. On
d. For

Hint: Prepositions are basically linking words. They help to identify the position of an object. They are placed before a noun or a pronoun. Prepositions are used to express the relation between the subject and the object.

Complete answer:
 Let us apply the given options and see which preposition makes the most sense.
> Option a is ‘at’. I waited at the bus stop for ten minutes. This makes perfect sense since people wait at a bus stop.

> Option b is ‘in’. A bus stop is usually an open space. So nobody waits in a bus stop. The preposition ‘in’ means that the object being referred to is a closed space. The cat sat in the box. A box is a closed space. Therefore ‘in’ is not the right answer.

> Option c is ‘on’. We use on to denote that we are on top of the object. The cat sat on the mat. A mat is a flat surface and the cat was sitting on top of it. Nobody stands on the shed of a bus stop. It is a funny imagery.

> Option d is ‘for’. I waited for the bus stop for ten minutes is wrong. Waiting for something means you are waiting for that thing to come to you. We do not wait for the bus stop to come to us. We go and stand at the bus stand and wait for the bus to arrive. Thus, it is a wrong answer as well.
Therefore, clearly, option a is the correct answer. I waited at the bus stop for ten minutes.

Note: Application of prepositions to the sentence and re-reading it helps to understand if the option is correct or not. Asking the questions ‘where’ and ‘when’ help us identify prepositions.