Halliday & Matthiessen (2014: 505):
We have now reached a point where we can relate these clauses to their close relatives that lie just beyond the bounds of expansion, on different frontiers. [i.e. process nominal groups and projections]
(1) Process nominal groups: we saw the turning of the boats. Here the process has been nominalised at the word rank, with turning as noun; cf. the departing/departure of the boats. The structure is that of a nominal group having a prepositional phrase with of as Postmodifier; the Complement of the of phrase corresponds to what would be the Complement if the process was realised as a clause. Examples:
| The building [ of [ the bridge ] ] | presented a problem.
Devaluation is taken to be | a humiliation [ akin to [ the defacing [ of [statues [ of [national heroes ] ] ] ] ] ] ] |
Where there would be an explicit Subject, if the process was realised as a clause, what corresponds to this is the ‘possessor’ of the process serving as Deictic in the structure of the nominal group, as in his handling of the situation, nobody’s peeling of potatoes is as careful as mine, or as Qualifier, marked by either by or of, as in Letters to the press indicate a ground-swell of rejection of this display, by catholic and non-catholic members of church communities and Yet another contributory factor is the disappearance of the horse from our farms.*
* Since a possessor can also be realised as an of phrase, this leads to the well-known ambiguity of expressions such as the visiting of relatives: going to visit relatives, or having relatives come to visit?