What's the best way should i study english language of office clerk when need to talk to clients for any types of company?

This is a type pf behavior that animals are born with and them to survive

Patient has just received an organ transplant which treatment would be most effective in preventing the patient’s body from

Approximately what portion of the foods that we eat have been genetically modified in some way? a.fewer than 10% b.about 50% c.nearly 100%