so sánh 

 a)     A = 2⁰ +  2¹ + 2² + 2³ + … + 2²⁰²² Và B = 2²⁰²³ - 1.

b)     A = 2021.2023 và B = 2022².

Exercise 1: Choose the words whose underlined part is pronounced differently from that of the others in each group.

1. A. special                            B. celebrate                             C. excited                                D. center

2. A. vegetable                        B. table                                   C. black                                   D. terrible

3. A. positive                           B. negative                              C. tug                                      D. future

4. A. puppet                            B. funny                                  C. schedule                             D. sunny

5. A. town                               B. flowers                               C. show                                   D. cow

6. A. live                                 B. dishes                                 C. ideas                                   D. milk

7. A. like                                 B. tick                                     C. kitchen                                D. dinner

8. A. east                                 B. clean                                   C. seat                                     D. great

9. A. spider                             B. slim                                     C. kind                                                D. striped

10. A kitchen                                      B. idea                                     C.dinner                                  D. village   

11.  A. black                           B. vegetable                            C. blanket                               D. blue

12. A. sandwich                      B. salad                                   C. later                                                D. jacket

13. A. herbs                             B. check                                  C. lemon                                  D. egg

14. A. talent                            B. lantern                                C. fashion                               D. always

15.  A. novel                           B. soccer                                 C. role                                     D.  comic