The Gardners and Fouts taught the chimpanzees signs from American Sign Language (ASL) by modeling (demonstration and getting the chimps to imitate) and physical prompting (directly manipulating the chimpanzees' hands into the required shapes). As the studies progressed, they found that the animals used ASL to communicate with each other. The apes created phrases from combinations of signs to denote new things that were brought into their environment. Loulis, Washoe's adopted son, learned basic ASL and over 70 signs directly from Washoe, without human involvement.