Real Grammar - Susan Conrad, Douglas Biber 2009

Discovery Verbs and Existence Verbs
Unit 3 Studies have shown…

What have you learned from your grammar textbook?

The present perfect tense is used for actions or states that happened or started at an unspecified time in the past. The action or state continues into the present or is still important in the present.

• He has written extensively about foreign affairs.

• The gap between rich and poor has widened.

What does the corpus show?

A

In academic writing, “discovery verbs” such as discover, find, and show are often used in the present perfect tense. These verbs tell the results of past research or studies, and they emphasize that the results continue to be important or relevant:

• Researchers have discovered how important relationships are with both colleagues and students.

• The International Labor Office has found this to be an international trend.

• Experiments have shown that plants can maintain rapid growth.

B

Discovery verbs can also occur in the simple present tense and simple past tense in academic writing. Discovery verbs in the simple present tense emphasize that results are currently true:

• Moorat’s study shows that older patients are especially prone to accidents.

In the simple past tense, these verbs suggest that the findings are not as important or relevant now:

• A research survey in 1986/87 showed that pupils frequently had no textbooks.

C

Another kind of verb is also common in academic writing: “existence verbs” such as represent and consist of. Existence verbs usually do NOT occur in the present perfect. These verbs usually occur in the simple present tense. They describe a current state or logical relationship.

• Our alphabetic writing system represents the sounds of speech. [NOT has represented]

• The rice in the field consists of plants of different types. [NOT has consisted of]

D

Frequency information. Here are lists of some of the most common discovery verbs and existence verbs used in academic writing:

• Studies of solidified lava flows have revealed evidence of many magnetic reversals.

• Subsequent work by Barron (1988) has shown that the oyster mushroom can utilize bacterial colonies.

• The Colville Lake community consists of seventy-five members of the Hare Indians.

• The accounts now contain the complete salary information for the month.

Activities

1 Notice in context: Read this paragraph from an academic text about research on neighborhoods. Circle the "discovery verbs" and underline the "existence verbs."

Despite problems, some researchers have discovered residents’ feelings about their neighborhoods by using questionnaires. Pacione (1984) revealed that residents’ satisfaction was influenced by traffic problems and street cleanliness. Dahmann (1985) has shown that residents’ satisfaction is inversely related to city size. Galster and Hester (1981) have found that certain groups (younger, those with many children) include lower levels of satisfaction in any context. These findings, of course, represent generalizations.

2 Analyze discourse: Look back at Activity 1 and at the discovery verbs and existence verbs you circled or underlined. Write the tense of each of these verbs in the margin. Draw an arrow between the verb and its tense.

3 Practice the structure: Complete each passage with the present perfect, simple past, or present tense of the verb in parentheses, use the meaning of the verb (discovery or existence) and the context (showing current relevance/importance or not) to determine the correct tense. Be ready to explain your choice to a partner.

4 Practice writing: use the notes in the box to write a paragraph about cigarette smoking in the united States. Use at least two discovery verbs in the present prefect to highlight results that continue to be relevant or important. Use at least one existence verb to describe a current state.

• 1964 U.S. Surgeon General’s study (and numerous later studies): cigarette smoking—serious health hazard with risks like lung cancer, heart disease, stroke, and birth defects.

• 1971: TV ads for cigarettes—banned due to health risks sales of cigarettes—banned to people under the age of 18

• 1980s: U.S. Congress requirement—stronger warning labels on cigarette ads

• 1988 U.S. Surgeon General’s study: nicotine (an ingredient in cigarettes)—addictive

• Now: health risks of cigarette smoking well known, smoking bans in public buildings in many cities, cigarette use still increasing with young people

The dangers of cigarette smoking are well researched; however, warnings by the Surgeon General of the United States have had mixed success in decreasing cigarette use in the United States. Many studies have shown that ...