Converse of object

• catch: Jenner identified that she had caught cowpox from the cows she handled each day.

Modifies a noun

• virus: For instance, Edward Jenner made the first successful vaccination in 1796 against smallpox by immunizing a patient with the cowpox virus.

• vaccine: Smallpox vaccination for infants over four months using Jenner's cowpox vaccine was made compulsory by the government in 1853.