17. A. our B. ours C. we D. us

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Question 17: A. our
B. ours
C. we
D. us

Question 18: A. could have
B. should have
C. would have
D. will have

Question 19: A. explore
B. to explore
C. exploring
D. explored

Question 20: A. scenic
B. boring
C. crowded
D. noisy

C. READING
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