As is known to all,we live in a world of germs(细菌).It is impossible to avoid exposure.Genetic makeups may give some people 1. advantage over others. However,it does not stop people 2. (become) sick.
All of us have been a victim of an 3. (ill) at some point in our lives.Moreover,it is likely that we 4. (get) sick again in the future.Our best chances of avoiding sickness 5. (be) by exercising and employing good 6. (habit).