Read the text and fill gaps with the proper grammatical form of the capitalized words.
1. are 2. having 3. will not feel 4. look 5. to teach 6. makes 7. pumping 8. strongest 9. stronger 10. stronger 11. bigger 12. increases 13. more 14. more easily 15. do 16. later 17. older 18. inflexible 19. active 20. better