The recipe for dinner in a university canteen is as follows: staple food: side dishes: staple food and side dishes mainly contain _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Protein, oil, sugar, vitamins, water and inorganic salts are the six nutrients needed by human body. Comparing the recipes, we can know that they also contain sugar and protein, so they are full of sugar and protein. By analyzing the nutrients contained in the recipe and the six nutrients needed by the human body, it is found that there are still vitamins in the dinner recipe, so vegetables can be used as side dishes.

So the answer is: sugar? Protein? vegetables