Chọn một phương án đúng A, B, C hoặc D ứng với từ hoặc cụm từ thích hợp để hoàn thành các câu sau.
10. They spent all day ______on the beach 
A. to swimming     B. to swim      C. swimming      D. swim 
11. If you want to pass the final exam, you ______study harder. 
A. can                    B. must            C. will                D. may 
12. ______air pollution is a major problem, many people still drive cars instead of using public transportation. 
A. Because            B. Although      C. Unless          D. Therefore 
13. "Caroline, remember to ______your coat before going out! It's very cold today," said the mother. 
A. put on                B. put off          C. take on          D. take off 
14. Maybe the baby is sick. I am going to ______her temperature. 
A. watch                 B. see                C. take              D. do