Exercise 5.2 A. In (1a) "on the corner" is not a modifier of "houses," but it should be. The PP restricts the meaning of the noun in the same way that an adjective does. The definite determiner indicates that its complement is uniquely identifiable in the discourse context and the uniquely identifiable set is not the set of houses but the set of houses on the corner. One substitution, if it is taken to substitute for N', shows that "on the corner" is adjoined to N':

1. John visited the old houses on the corner and Bill visited the new ones.
2. John visited the houses on the corner and Bill visited the ones in the middle of the block.

B. One substitution shows that "little girl" should be a constituent and "pizza with anchovies" should be a constituent. Do so substitution shows that "that pizza with anchovies" should be a constituent. None are in (2).