Question 19: 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: Paper was so expensive during the Middle Ages that it has to be used sparingly.
The time in the sentence is the Middle Ages: medieval, meaning past.
=> The verb “have” needs to be conjugated in the past simple, not the present simple.
=> Answer B is the option that needs to be corrected and changed to had.
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