Height is 'a function of' age in children. [=the height of children increases as their age increases]
His bad health has prevented him from being able to 'function' effectively in recent weeks.
Her chief/main/primary/principal 'function' is to provide expert legal advice.
(..) Time to wake him up. Excuse me? What are you doing here? Babe, where are you going? "Louis." Subject regaining cognitive functions. Whats happening? Where am I? You were in an explosion, Alex. You're in a hospital. Where? (..)2014 RoboCop