What is the difference between gerund and infinitive? How are they formed? Give some examples of sentences with both forms.

Gerund is a verb itself but with the ending -ing it is a noun in the sentence (playing). Infinitive is the initial form of the verb, and it needs the preposition to before it (to play). One of the most important differences between these forms is that the gerund is used after the prepositions of place and time (I felt happy after finishing this work). Infinitive is used after the adjectives (It was hard to do this task).