Choose the appropriate preposition for the given sentence:
The police were ______ the cheats for many years.

- The given sentence is saying something about the police and the cheats.
- The use of the word ''cheats'' in the sentence indicates the people who behave dishonestly in order to gain an advantage.
- The sentence tells that the police were trying to catch the cheats for many years.
- Therefore, the most appropriate preposition to be filled in the blank is 'after'.
- Complete Sentence: The police were after the cheats for many years.