6. B. danced ⇒ was dancing
7. A. What an ⇒ What (Bỏ "an")
8. A. Read ⇒ Reading
9. C. best ⇒ better
10. A. Despite ⇒ In spite
11. A. to carve ⇒ of carving
12. A. flew ⇒ was flying
13. D. history ⇒ historical
14. B. to not take off ⇒ not to take off
15. A. three-weeks ⇒ three-week