Although gestures are a means of communication for everyone, they are essential for the hearing impaired. In other comma splices , the comma is accompanied by a joining word that is not a coordinating conjunction. Gestures are a means of communication for everyone, however, they are essential for the hearing impaired. The word however is a conjunctive adverb, not a coordinating conjunction. When used to join independent clause, a conjunctive adverb must be preceded by a semicolon.
All pronouns have antecedents.
An antecedent is the noun which the pronoun refers to or replaces. A pronoun and its antecedent agree when they are both singular or both plural. Martha decided to have a garden party to celebrate her birthday. She used fresh flowers to decorate the tables, and stayed pretty all evening. After a dove and a canary came out of the hat, immediately flew out over the auditorium.