I asked a question regarding PP complements the other day and I believe I now have a better handle on that. But I am still scratching my head over this paragraph from CGEL:
Within the category of internal dependents we will draw a distinction between modifiers and complements. The pre-head dependents in [7] are modifiers, while complements are seen in the finance minister, our legal advisor, and the like. (Cambridge Grammar of the English Language (2002), p.331)
I thought "finance" in "the finance minister" was a noun adjunct, and so was "legal" in "our legal advisor", because if you take them out what you get is still normal, meaningful NPs. A minister is a minister, and that one just happens to be responsible for finance. But in Huddleston and Pullum's description, "finance" and "legal" are indispensable to the NPs. Are they integral parts of their respective NPs because they bond with the head nouns? But why?