Ответ:
1. breathe
2. exercise
3. recover
4. suffer
5. cough
Объяснение:
1. It can be difficult to breathe at the top of a very high mountain.
2. I know I should exercise more often, but it's not easy to find the time.
3. It will take you a few weeks to completely recover from your illness.
4. Both my grandparents suffer from arthritis.
5. If you have to cough, please put your hand in front of your mouth!