Phrases and clauses that are involved in this sort of modification are referred to as being embedded (in other words, rankshifted
or functioning as a constituent in a nominal group), for example, the phrase on the hill in The house on the hill is for sale., and the clause that had just been cleaned in They drove the car that had just been cleaned.
The latter are rankshifted into the nominal complement slot of clefts, whereas the antecedents of NRRCs display the structural assembly congruent with their rank.
However, the "non-NP" units functioning as complement in clefts are rankshifted into the nominal complement slot and are in this sense "nominalized" (Halliday 1985: 219).
I propose that it is precisely the "rankshifted," nominalized, status of such antecedents in clefts that explains their resistance to relative adverbs such as when, where, etc.
If the complement in clefts is realized by a rankshifted element such as adverb, prepositional phrase, or clause, then its semantic profile is that of a -- reified -- entity.
Prepositional phrases and clauses are rankshifted into the nominal complement slot and are reclassified as definite NPs.
Note also that the enumerating complement in there clefts accepts fewer types of rankshifted units than the identifying complement in it clefts.
But there can be no doubt that it clefts allow for a greater variety of rankshifted units than there clefts.
At the level of the phrase, we have an instance in which a phrase is being postmodified by a clause: 'to be in the removal of nutrients...' These are tactic and embedding or rankshifted
relations--relations argued by Downing & Locke (2006: 275) as reflecting the degrees of the integration of events from the point of view of the speaker with embedding encoding a tighter integration.