There are three types of participles in English: present, past, and perfect. The present participle ends in "-ing" and is used in progressive tenses, adjectives, and gerunds. The past participle is used in perfect tenses and the passive voice. Both the present and past participles can be used to shorten sentences by combining clauses with the same subject. The perfect participle combines clauses where one action is completed before another starts. Participles are useful for combining information concisely in writing.