Halliday & Matthiessen (1999: 27):
There are many examples of cryptotypes in this sense, both as classes and as systems (i.e. cryptoclasses and cryptosystems), in our ideational semantics. For example:
- proces types: doing & happening / sensing / saying / being & having
- transitivity model: ergative / transitive
- projections: locutions / ideas
- expansions: elaboration / extension / enhancement
- number: plural / non-plural; singular / non-singular