1. Adverbs and adverbial
What about "Wendy could see a house at the end of the street“? What is ‘at the end of the street?
This sentence is ambiguous.
First reading: the whole stretch is a sentence with 'Wendy' as subject. Then we have a modal verb and a main verb, followed by the noun phrase 'a house at the end of the street'. This noun phrase functions as the object in the sentence. Within that noun phrase there is a preposition phrase ('at the end of the street') which functions as postmodifier of the noun 'house'.
Second reading: 'Wendy' is again the subject. And again we have a modal verb and a main verb, followed by the noun phrase 'a house'. This noun phrase functions as the object in the sentence. Then we have 'at the end of the street'. This is a preposition phrase which functions as adverbial in the sentence. Under this reading Wendy was at the end of the street when she saw the house.  We can re-order this sentence as 'At the end of the street, Wendy saw a house'.