This document discusses the differences between gerunds and infinitives in English grammar. It begins by explaining that gerunds are verb forms ending in "-ing" that function as nouns, and infinitives are the basic form of a verb preceded by "to". It then provides examples of gerunds and infinitives being used as subjects, objects, objects of prepositions, and subject complements. The document notes some verbs take gerunds or infinitives and others can take both. It concludes with practice sentences requiring the use of gerunds and infinitives in different roles.