Unit 1

1.younger

2. older

3. taller

4. shorter

5. longer

6. thinner

7. heavier

8. bigger

9. smaller

10. stronger

11. dinosaur

12. hall

13. metre

14. than

15. both

16. kilogram

17. countryside

18. lower

19. shadow

20. smarter

21. become

Unit 2

1. cleaned

2. stayed

3. washed

4. watched

5. had

6. slept

7. read

8. saw

9. last

10. yesterday

11. before

12. drank

13. show

14. magazine

15. better

16. faster

17. hotel

18. fixed

19. broken

20. lamp

21. loud

22. enjoy

23. stay

Unit3

1. went

2. camp

3. fish

4. road

5. hurt

6. ate

7. took

8. bought

9. gift

10. fell

11. off

12. Labour Day

13. mule

14. Turpan

15. could

16. till

17. beach

18. basket

19. part

20. licked

21. laughed

Unit4

1. dining hall

2. grass

3. gym

4. ago

5. cycling

6. ice-skate

7. badminton

8. star

9. easy

10. look up

11. Internet

12. different

13. active

14. race

15. nothing

16. thought

17. felt

18. cheetah

19. trip

20. woke

21. dream