Wash the fruit and peel the mandarin orange. Prepare a large glass jug with a wide “mouth” (big enough for a large spoon, or better still a ladle, to pass through it). Cut the oranges and one of the lemons – with the rinds on – into thick slices, then cut each slice in half and put them in the bottom of the jug, together with the mandarin segments and the apples (also with the skin on if you like) without the core, cut into segments and then into pieces. Add the sugar and the juice of half a lemon and stir delicately. Pour the bottle of grape juice into the jug and put it in the fridge, to infuse, for two or three hours.
When you want to serve the Sangria, add ¾ of a bottle of Spumante (or the amount you prefer for the "right" alcohol content) pouring very slowly so as not to create too much froth. Another quick stir, taking care not to take the “fizz” out of the Sangria… and all that’s left to do is fill the glasses, decorated with a slice of orange (cut a small slit in one side), a long handled spoon and a cocktail straw.
Another idea is to prepare an alcohol-free version for children. The method is the same: you need to increase the quantity of grape juice (maybe take the skin off the fruit) and as a final “touch”, to make them feel big, a drop of fizzy water (or even soda water)!