The man walks to the house. The dog beside him trotted, its tongue hanging out. The house stood silently as it had for over a hundred years. The dog runs to the front door, his tail a fan in the hot air.

The preceding paragraph makes me tense because of the switching of verb tense from present to past to present. Oh, someone said he doesn't know what I mean. Let's see if I can explain about verb tense, but not in depth because that would be confusing at this point. The main topic of discussion will be present and past tenses, with just a little information about the others.

First, what is verb tense? Verbs change form to show time. The six main forms are called tenses. We use four principal parts of a verb to create those six tenses: base or present form; past form; present participle; and past participle. The present participle and past participle must always have a helping verb to be used as a verb. Clear as mud, right? In other words, participle forms may be used as other parts of speech, not just verbs in a sentence. That subject is a matter for another time, though.

The six tenses show time from present to past to future. A brief explanation of the six follows. Irregular verbs differ in forms of tenses, and a writer should check a grammar book for the forms of irregular verbs:

Present tense shows action or condition existing at the present time. It uses the base or present form without any helping verb or verbs. The third-person-singular form of the present tense often adds -s or -es to the base form; irregular verbs differ.

Past tense shows action or conditions beginning and ending in the past. The past form of the verb, which is used, doesn't have any helping verbs.

Future tense involves action or conditions that will begin in the future, that has not yet occurred, using the helping verb will or shall before the base form of the main verb.

Present Perfect Tense uses the helping verb have or has before the past participle of the main verb. This tense shows action that started in the past and continues into the present, or which happened at an indefinite time in the past.

Past Perfect Tense shows action that started in the past and ended before another past action began. The helping word had is used before the past participle of the main verb.

Future Perfect Tense uses the helping verbs will (or shall) and have before the past participle form of the main verb. It shows a future action that will have ended before another begins.

For writing, though, we usually use present tense or past tense for the majority of the exposition or narrative. Not being consistent with verb tenses causes problems.

Using present tense is difficult to use effectively. Everything has to be happening in the present, not in the past. Many writers who start using present tense discover they slide into past tense and then perhaps back to present, as in the illustration given earlier. Many readers don't feel comfortable reading something written in present tense. When a reader doesn't, then the author has lost his audience.

Most authors use past tense in their work. They and their readers feel more comfortable doing so, sticking to the same tense made easier, too.

Good writing requires the author keep the writing consistent, using either present tense or past tense without switching from one to the other. A few writers are able to write one portion in one tense and another portion in another tense, but it takes a very skilled author to do so effectively and correctly.

An author fails when not writing something that others want to read. A lack of consistency in verb tense causes readers to stop reading because of confusion. Some work on the writer's part can result in a work that others do want to read and that they can enjoy.

Sources:
1. Notes and lesson plans by Vivian Zabel
2. Writer's Companion: High School, Prentice Hall