Analysis: When the whole surface is painted red, only those "stuck together" faces (also called touching faces) are not painted. Each small cube has six faces. Subtract the number of unpainted faces to get the number of painted faces. Just answer the question with meaning.

Solution: Solution: As shown in the figure, each cube is marked with a number:;

(1) There are 6 small cubes painted red; Only 1.

(2) There are 2, 3, 5 and 7 small cubes, all of which are painted red; * * * There are four.

(3) There are 1, 4, 8 small cubes, and five sides are painted red; * * * There are three.

So the answer is: (1)1; (2)4; (3)3.

Comments: The key to solve this problem is to make it clear that the painted faces are subtracted from the total number of cubes.