rolling words by ligang deng from china

Plenty of wood is consumed in printing the learning material as lots of people are learning foreign languages. The combination of word lists and toilet rolls would probably lead to a remarkable decrease in wood consumption.
Language learning should occur in every aspect of our daily life, even in bathroom. And green life can coexist with language learning.
It is interesting that we may slow down the rate of consumption of toilet rolls when it is not so quick to grasp the words printed on them.
This design is believed to be feasible and practicable when referring to industrialization.We can buy toilet rolls in a bookstore, and word lists in a supermarket as well.