According to CaGEL* (e.g. p.636 ff), prepositions can take predicative complements, as in
[1] She worked as a waitress
[2] He passed for dead
[3] I took you for granted
[4] They left him for dead
[5] I love you as a friend
Now, I get how these are predicatives, but I'm uncertain as to how to analyse the PPs as wholes. I'm thinking they are complements in [1]-[4] and adjunct in [5] – is this correct? And, if so, what kinds of complement are we dealing with in [1]-[4]?
*Huddleston, R., and Pullum, G. K., 2002. The Cambridge Grammar of the English Language. Cambridge: Cambridge University Press.