13. Accommodation in London — very expensive. a. is b. are c. has d. have 6. The flight _____ at 6.10 has been delayed. a. leave b. leaves c. leaving d. left 15. ______ is a large hole in the side of a mountain or under the ground. a. Waterfall b. Cave c. Bay d. Lake 18. After ______ breakfast, I went out for a walk. a. finish b. having finished c. finished d. had finished 19. ______ is a type of white or gray stone containing calcium, used for building and making cement. a. Slope b. Limestone c. Site d. Sand 20. China has huge _____ and onshore oil reserves. a. seaside b. remote c. outside d. offshore 26. Da Lat is known like a city of pines, waterfalls and flowers.( tìm lỗi sai) 27. There are notices showing arrivals and departs of trains.( tìm lỗi sai)