Trout and many other kinds of fishes are able to change their colors quite rapidly and they do this by contracting or expanding these pigment cells.
(Trout and many other kinds of fishes; are; able to change their colors quite rapidly) (Trout and many other kinds of fishes; to change quite rapidly; their colors) (they; do; this) Context(they do,List([87, 94))):(they; do this by contracting; )
they do,List([87, 94))
Trout and many other kinds of fishes Trout and many other kinds of fishes they they
are to change quite rapidly do do this by contracting
able to change their colors quite rapidly
their colors
this