Read the definitions carefully and select the correct words.
1. able to move quickly and easily
2. the ability to move quickly and easily
3. to move part of your body so that it is not straight or so that you are not upright
4. no longer straight
5. happening regularly or all the time
6. something that is crucial is extremely important, because everything else depends on it
7. needing a lot of ability, effort, or skill
8. to plan or invent a new way of doing something
9. extremely important and necessary
10. very keen to do something or achieve something, especially because you find it interesting or exciting
11. the reason why somebody does something or behaves in a particular way
12. a type of exercise in which you lie facing the ground, and push your body up with your arms
13. if someone or a part of their body is stiff, their muscles hurt and it is difficult for them to move
14. to become stronger or make something stronger
15. to straighten your arms, legs, or body to full length
16. to produce a new idea, name etc by thinking
17. extremely important and necessary for something to succeed or exist
18. to do gentle exercises to help your body relax after doing a particular sport or activity
19. to do gentle physical exercises to prepare your body for dancing, sport etc
20. to make someone or something less powerful or less important, or to become less powerful
21. to become wider, or to make something wider
22. to make your body fit and strong by doing exercises
23. a period of physical exercise, especially as training for a sport