高二上学期期中考试英语
试题第一节 单项填空（共15小题；每小题1分，满分15分） 21. we can never expect __________ bluer sky unless we create _______ less polluted world. a. a; a b. a; the c. the; a d. the; the 22. some children want to challenge themselves by learning a language different from _______ their parents speak at home. a. what b. that c. which d. one
