Prepositions may be the most difficult aspect of English grammar to learn, as using them is not a matter of simply memorizing some simple rules. Click on the links below to access a variety of resources on using prepositions in English. devotes a page to the three most common Prepositions “On,“ “At,“ and “In.“

English Grammar Online has a page of rules and links to several practice exercises on quantifiers.

Perfect English Grammar has a page describing the rules for using prepositions, and a series of exercises to practice what you’ve learned also has a set of rules for prepositions. offers many practice exercises on Prepositions and Phrasal Verbs.