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: Students suppose (A) to read all the questions (B) carefully and find out (C) the answers to them (D).
Answer A.
We have the phrase: be supposed to do sth: to have a duty So: suppose => are supposed
The students are supposed to read all the questions carefully and find the answers
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