21. You can go to the movies with me, .................... you can go to the concert alone. A. and B. or C. so D. therefore 22. He was able to go to university .................... his aunt’s help. A. Because B. Because of C. if D. and 23. The boy can’t reach the shelf .................... he’s not tall enough. A. because B. although C. even though D. and 24. Nam failed the final exam .................... he was lazy. A. while B. though C. because D. but 25. We didn’t go for a walk .................... it was very cold. A. though B. because C. but D. so 26. I’m learning English .................... I want to get a better job. A. or B. because C. therefore D. but 27. The flight was delayed ……………. ..the fog. A. in spite of B. because of C. though D. since 28. Huong didn’t participate in the contest …………… her lack of confidence. A. because B. because of C. since D. despite 29. He hid that letter in a book …………. no one could read it. A. so that B. because C. although D. in spite of 30. ………………. Nam was unable to see anything, he knew someone was in his room. A. because B. In case C. If D. Even though