All 3 Uses of

demonstrate
in
Rose Red

Sukeena-or whoever she had become-snapped her head so quickly then I feared her unreal, for it was with the degree of movement an owl might demonstrate, and it turned straight back behind her.†
Chpt 4

demonstrate = show

Now it is that I can understand Tina's calm that day, the almost perverse peace she demonstrated upon our arrival.†
Chpt 7

demonstrated = showed

For her part, April demonstrated no enthusiasm for the change of environment (something I'd secretly hoped for!)†
Chpt 7 *

Definitions:

(1) (demonstrate as in: It demonstrates my point.)
to show
The exact meaning of this sense of demonstrate can depend upon its context. For example:
- "I will demonstrate how to throw a Frisbee." -- show how to do something
- "I will demonstrate how much quicker the new computer is than the old one." -- show how something works
- "Her questioned demonstrated that she was listening and thinking deeply about what was said." -- showed to be true or proved
(2) (demonstrate as in: demonstrate to protest)
a public display supporting a cause -- usually joining with others in a political protest