Water is the only substance that can be three different forms at normal human temperatures: liquid, solid, or gas.
(Water; is; the only substance that can be three different forms at normal human temperatures: liquid, solid, or gas) (the only substance; can be; three different forms at normal human temperatures)
Water the only substance
is can be
the only substance that can be three different forms at normal human temperatures: liquid, solid, or gas
three different forms at normal human temperatures