Study the modal forms in blue in sentences 1-5. Then choose the correct
options in the rules.
1 Doctors believe taking more and more
medication can't be good.
2 Some doctors suggest exercise could be a more
effective treatment for certain health conditions.
3 Exercise might also lead to a reduction in painful
inflammation.
4 If you're ill, your body must be out of balance.
5 Swimming in cold water in lakes and the sea may
be a better treatment.
