This document discusses the use of gerunds and infinitives in English. It provides examples of using the -ing form of a verb (gerund) after prepositions like "in", "at", "with", as well as after verbs like "like", "enjoy", "love", "hate", "finish", "go", "stop". It also provides examples of using "to + verb" (infinitive) after verbs like "want", "hope", "learn", "need", "forget", "decide", "promise", "would like", "wouldn't like", "would hate". The document explains that gerunds are used to talk about activities and infinitives are used