When deriving the formula of cylinder volume, the cylinder can be cut and spliced into an approximate cuboid. The base area of approximate cuboid is equal to the base area of cylinder, and the height of approximate cuboid is higher than the height of cylinder, so the volume of cylinder = base area × height, which is expressed by letters as V = SH. This derivation process embodies the mathematical thought of transformation.

So the answer is: bottom area, bottom area, high, high, bottom area, high, sh, transformation.