Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
PARTICIPLES
English verbs (e.g., study, swim) have present participles ending in -ing (studying, swimming), and past participles ending in -ed (studied) or, in strong verbs, in a distinctive morphological form involving either a change of vowel, the dental suffix, some combination of the two, or another distinctive form (swum, fit, slept, driven). Participles are forms of verbs that can function as nouns (present participles so functioning are called gerunds), as in Jogging is my usual exercise, or as adjectives, as in He goes at a jogging pace. The present participle is also used with auxiliaries to form the progressive aspect of the verb: She was writing a short story. The past participle is used with auxiliaries to form the so-called perfect tenses: She has written several stories. We had studied one of Emerson’s essays. See also DANGLING MODIFIERS; GENITIVE BEFORE A GERUND.
