Prepositions "On," "At," and "In"
A preposition is a word that

links a noun, pronoun, or noun phrase to some other part of the sentence.
Prepositions can be tricky for English learners. There is no definite rule or formula for choosing a preposition. In the beginning stage of learning the language, you should try to identify a preposition when reading or listening in English and recognize its usage.
A preposition is used to show direction, location, or time, or to introduce an object.

Quiz Time:

Choose a correct preposition in the sentence.

1)I want to lose 5 kilograms________(on, at, in) one month.

2)Could you get me these pants_______(on, at, in) a larger size?

3)She seems to be interested______(on, at, in) Psychology.

4)I will come to pick you up______(on, at, in) 2 pm tomorrow.

5)This class will be held_____(on, at, in) Mondays.