Perfect tenses assist in determining the verb or the action word as something that previously happened or is created, therefore the term ‘perfect’. If it is present perfect tense, it indicates that the action was previously done approximately to the present (has/have with past participle). If it is past perfect tense, the action is now finished approximately to the past (had with past participle and if it is future perfect tense, the action is simply relative to the future (will have with past participle).
b. When two independent clauses are closely related to each other and are joined by a conjunctive adverb of two syllables or more, place a semicolon before the conjunctive adverb and a comma after it.