In English grammar, the voice of a verb describes the relationship between the action (or state) that the verb expresses and the participants identified by its arguments (subject, object, etc.). Verbs are either active or passive in voice. In the active voice, the subject and verb relationship is straightforward: the subject is a do-er. In the passive voice, the subject of the sentence is not a do-er. It is shown with by + do-er or is not shown in the sentence. Passive voice is used when the action is the focus, not the subject. It is not important (or not known) who does the action. Also know about Adverbs(Comparative-Comparison) and Subject Verb Agreement and many more.