Заполните пропуски модальными глаголами can, may, must, should. 1. In man, obstruction of the common duct ... produce

1. In man, obstruction of the common duct may produce abdominal symptoms and increase of serum amylase. 2. An ulcer may be only on an epithelial or mucosal surface. 3. Appendicitis can be of different grades of intensity. 4. In an attack of acute appendicitis no food must be taken by mouth and no water except in very small sips. 5. There was general agreement that the patient\'s diet should be rich in protein and carbohy drates, but poor in fat.