9. Answer 4: Error – article / adjective position There was a steady increase in sales of cars.
10. Question 5: The number of people living in the city centre declined sharply.
11. Answer 5: Correct The number of people living in the city centre declined sharply.
12. Question 6: There was a sharply decline in the amount of land available for building.
13. Answer 6: Error – adjective / adverb There was a sharp decline in the amount of land available for building.
14. Question 7: During the period 1970 to 1995 number of people travelling abroad increased gradually, but then fell sharply in 1996.
15. Answer 7: Error - article During the period 1970 to 1995 the number of people travelling abroad increased gradually, but then fell sharply in 1996.
16. Question 8: Sales of computers rose dramatically from just under 1 million per year to over 3 million per year between 1995 and 2005.
17. Answer 8: Correct Sales of computers rose dramatically from just under 1 million per year to over 3 million per year between 1995 and 2005.
18. Question 9: There was a steady decline of sales of houses between 2006 and 2008, but then sales increased slightly in 2009.
19. Answer 9: Error - preposition There was a steady decline in sales of houses between 2006 and 2008, but then sales increased slightly in 2009.
20. Question 10: The percentage of people who got married in the USA slight declined in the 1990s but rose again in the 5 year period from 2000 to 2005.
21. Answer 10: Error – adjective / adverb The percentage of people who got married in the USA declined slightly in the 1990s but rose again in the 5 year period from 2000 to 2005.