Dear Friends,
Here is a detailed explanation to this question-
nocilis wrote:
Five hundred million different species of living creatures have appeared on Earth, nearly 99 percent of them vanishing.
(A) Five hundred million different species of living creatures have appeared on Earth, nearly 99 percent of them vanishing.
(B) Nearly 99 percent of five hundred million different species of living creatures that appeared on Earth have vanished.
(C) Vanished are nearly 99 percent of the five hundred million different species of living creatures that appeared on Earth.
(D) Of five hundred million different species of living creatures that have appeared on Earth, nearly 99 percent of them have vanished.
(E) Of the five hundred million different species of living creatures that have appeared on Earth, nearly 99 percent have vanished.
Meaning is crucial to solving this problem:
Understanding the intended meaning is key to solving this question; the intended meaning of this sentence is that five hundred million different species of living creatures have appeared on Earth, and of these species, nearly 99 percent have vanished.
Concepts tested here: Meaning + Tenses + Verb Forms + Awkwardness/Redundancy• The introduction of present participle ("verb+ing"- “vanishing” in this case) after comma generally leads to a cause-effect relationship.
• The present perfect tense (marked by the use of the helping verb “has/have”) is used to describe events that concluded in the past but continue to affect the present.
• The simple past tense is used to refer to actions that concluded in the past.
A: This answer choice alters the meaning of the sentence through the phrase "nearly 99 percent of them vanishing"; the use of the "comma + present participle ("verb+ing" - "vanishing" in this sentence)" construction incorrectly implies that five hundred million different species of living creatures have appeared on Earth, and
as a result, nearly 99 percent these species have vanished; the intended meaning is that five hundred million different species of living creatures have appeared on Earth, and,
as a separate action, of these species, nearly 99 percent have vanished; please remember, the introduction of present participle ("verb+ing"- “vanishing” in this case) after comma generally leads to a cause-effect relationship.
B: This answer choice alters the meaning of the sentence through the phrase "99 percent of five hundred million"; the omission of the word "the" incorrectly implies that
more than five hundred million different species of living creatures have appeared on Earth, and of a
particular subset of these species, nearly 99 percent have vanished; the intended meaning is that
a total of five hundred million different species of living creatures have appeared on Earth, and of these species, nearly 99 percent have vanished. Further, Option B incorrectly uses the simple past tense verb "appeared" to refer to an action that concluded in the past but continues to affect the present; remember, the present perfect tense (marked by the use of the helping verb “has/have”) is used to describe events that concluded in the past but continue to affect the present, and the simple past tense is used to refer to actions that concluded in the past.
C: This answer choice incorrectly uses the simple past tense verb "appeared" to refer to an action that concluded in the past but continues to affect the present; remember, the present perfect tense (marked by the use of the helping verb “has/have”) is used to describe events that concluded in the past but continue to affect the present, and the simple past tense is used to refer to actions that concluded in the past. Further, Option C uses the passive voice construction "Vanished are nearly 99 percent", leading to awkwardness and redundancy.
D: This answer choice alters the meaning of the sentence through the phrase "Of five hundred million"; the omission of the word "the" incorrectly implies that
more than five hundred million different species of living creatures have appeared on Earth, and of a
particular subset of these species, nearly 99 percent have vanished; the intended meaning is that
a total of five hundred million different species of living creatures have appeared on Earth, and of these species, nearly 99 percent have vanished. Further, Option D uses the needlessly wordy phrase "nearly 99 percent of them ", leading to awkwardness and redundancy.
E: This answer choice uses the phrases "Of the five hundred million" and "nearly 99 percent have vanished", conveying the intended meaning - that
a total of five hundred million different species of living creatures have appeared on Earth, and,
as a separate action, of these species, nearly 99 percent have vanished. Further, Option E correctly uses the present perfect tense verb "have appeared" to refer to an action that concluded in the past but continues to affect the present. Additionally, Option E is free of any awkwardness and redundancy.
Hence, E is the best answer choice.To understand the concept of "Simple Tenses" on GMAT, you may want to watch the following video (~1 minute):
To understand the concept of "Present Perfect Tense" on GMAT, you may want to watch the following video (~1 minute):
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To understand the concept of "Comma + Present Participle for Cause-Effect Relationship" on GMAT, you may want to watch the following video (~3 minutes):
All the best!
Experts' Global Team
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