Answer:
- <em>The verb </em><em><u> went </u></em><em> must be changed to maintain verb tense consistency.</em>
Explanation:
<em>Verb consistency</em> means that the verbs in the sentence must agree in number (singular/plural) and tense (present/past/future/perfect/progressive).
<em>Verb tense consistency</em> requires that the verbs in clauses of the same sentence agree in tense.
This is, you must not change from one tense to another.
In the sentence "<em>There</em><u><em> are </em></u><em>more private K-8 schools than there</em><em><u> are </u></em><em>private schools for grades 9-12, so many students who</em><em><u> attend </u></em><em>private grade school </em><em><u>went </u></em><em>on to attend a public high school</em>", the two <u> </u><u><em>are </em></u>and<u> </u><em><u>attend</u></em><u> </u>are in present, while<u><em> went </em></u>is in past tense.
Using <u><em>went</em></u>, then breakes the consisteny.
Thus, went must be changed to maintain verb tense consistency.