Halliday & Matthiessen (2014: 504):
[relational: attributive]
It was careless of him [[ = to put another man’s helmet on ]]
[relational: identifying]
[[ Not being much of a reader]] hardly affected the ascent of George W. Bush or his father.
These examples show typical contexts for such nominalisations: relational clauses, especially attributive ones where the attribute is an evaluative term and identifying ones where they are related to a nominalisation. There is one other common environment, namely that of clauses of perception, either mental (inert perception) or behavioural (active perception). Examples:
[behavioural + mental: perceptive]
We were watching [[ = the catch being brought in]] and you could see [[[ = the boats turn || × as they rounded the headland]]]
[behavioural: perceptive]
We went and watched [[ = these kids try to produce ‘Hair’ ]] .
[mental: perceptive]
Here you can see [[ = beer being brewed ‘on sight’]]