Question 30: Mark the letter A, B, C, or D on your answer sheet to indicate the undelined part that needs correction in each of the following questions: Rocks have forming, wearing away and re-forming ever since the Earth took shape
Change have forming to have been forming. Based on the word since, the verb must be used in the perfect form.
The rocks have continued to form, wear down, and re-form since the existence of the Earth.
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