V as n
The 'function' groupThese verbs are concerned with having a role or a function. The prepositional phrase indicates what someone or something is.
All these verbs are link verbs (see Chapter 5).
act double figure function operate serve double up
Players act as their own referees, and altercations and bad language are virtually unknown.
A basic walking boot with tough leather uppers can double up as a digging boot.
Monosodium glutamate is a food additive that functions as a flavour enhancer.