is a related group of words that functions as a part of speech and
does not contain both a subject and a verb.
➲ Verb phrases
do not contain a subject. Examples of verb phrases
include has been laughing, will remain, and does believe.
➲ Prepositional phrases, such as the adjective phrase and the adverb
phrase, do not have a subject or a verb. Examples of prepositional
phrases are in the beginning, at the end, and after the trial.
➲ Participial phrases function as adjectives. In the sentence, ‘‘Walking
home after the movie, Joe felt happy,’’ the participial phrase is
Walking home after the movie, and the participle is Walking.
➲ Gerund phrases function as nouns. Gerund phrases can be used as
subjects, predicate nominatives, direct objects, indirect objects, and
objects of the preposition. In the sentence, ‘‘Walking home from the
movies was a good time for Joe and his friends,’’ the gerund phrase used
as a subject is Walking home from the movies.
➲ Infinitive phrases function as nouns, adjectives, or adverbs. In the
sentence, ‘‘To beat the old record was Nina’s goal,’’ the infinitive phrase
is To beat the old record, and the infinitive is To beat.
➲ Appositive phrases describe or identify another noun or pronoun
in the sentence. In the sentence, ‘‘Lake Harris, our favorite vacation
spot, is off the beaten path,’’ the appositive is spot, and the appositive
phrase is our favorite vacation spot.
The Dynamo 2
How Electricity is obtained on a Large Scale
As has been said, the arrangement of the preceding Section is a dynamo in miniature. Every dynamo, no matter how complex its structure and appearance, consists of a coil of wire which can rotate continuously between the poles of a strong magnet. The mechanical devices to insure easy rotation are similar in all respects to those previously described for the motor.
The current obtained from such a dynamo alternates in direction, flowing first in one direction and then in the opposite direction. Such alternating currents are unsatisfactory for many purposes, and to be of service are in many cases transformed into direct currents; that is, current which flows steadily in one direction. This is accomplished by the use of a commutator. In the construction of the motor, continuous motion
in one direction is obtained by the use of a commutator; in the construction of a dynamo, continuous current
in one direction is obtained by the use of a similar device.
FIG. - A modern electrical machine.