What is the function of the underlined nouns in the following sentences. What is the function of the underlined nouns in the following sentences

What is the function of the underlined nouns in the following sentenceswhat is the function of the underlined nouns in the following sentences                                                                                                                                   1 she is a nurse
   2 Your jeans   are to tight 
   3 John threw the ball
   4 This jacket looks very nice and suits you well 
  5 Tourism is the main industry in the region