The FreeSprite() function returns a hardware sprite allocated with
GetSprite() to the system so that GELs or other tasks can use it.  After
you call FreeSprite(), the GELs system can use it to allocate VSprites.
The syntax of this function is:

    WORD sprite_number;

    FreeSprite(sprite_number);

The sprite_number argument is the number (0-7) of the sprite to be
returned to the system.