SOAK THE CLOUD EAR FUNGUS in warm water for at least 15 minutes. Rinse them several times in cold running water to remove any sand. Drain thoroughly and set aside. If you are using the Chinese longbeans, trim the ends and cut them into 3-inch segments. If you are using green beans, trim the ends and cut them in half. Peel off the tough outer skin of the silk squash and cut the vegetable at a slight diagonal into 2-inch pieces. Heat a wok or large saute pan until hot and add the oil. Put in the shallots, garlic, ginger, cloud ears and longbeans. Stir-fry for 1 minute, then add the silk squash, oyster sauce, rice wine, soy sauce, salt, sugar and chicken stock. Cook over high heat, uncovered, until the vegetables are tender, about 5 minutes. Serve at once.