Generalizing the use of descriptive adjectives through modelling.

Two children with intellectual disabilities watched an adult model short sentences. The adult always used color or size words like “red truck” or “big dog.”

After each model, the child copied the sentence. Training moved through sets of toy animals. A multiple-baseline design showed the sequence clearly.

Both kids jumped from almost zero adjectives to about 80 % in just a few sessions.

When new, untrained animals appeared, the children still said things like “small cat” or “green frog.” Generalization was strong and immediate.

Mazur et al. (1992) later showed peers can do the teaching. Their students with moderate ID learned first-aid words from classmates and still used them at home. The 1975 study opened the door; the 1992 study walked through it.

Pisman et al. (2020) pushed the idea further. Moms embedded language in play and kept the fun alive. Both papers kept the multiple-baseline design and the clear generalization, proving the method travels across people, places, and decades.

Herrnstein et al. (1979) looked at sharing instead of adjectives. They also saw that teaching one form of language (verbal sharing) made the physical act spread. The pattern is the same: teach a word, watch the skill travel.

You can add a quick model-imitate loop to any toy play or table work. After a few adult-led examples, the child is likely to use new describing words with new items. No extra probes, no fancy software—just watch generalization happen.