Although the text of this has been lost, we know enough about it from quotes in other works to know that it was an elementary text. Yang says that he wrote it:
Kahit na ang teksto ng mga ito ay nawala, alam namin tungkol sa sapat na ito mula sa iba pang mga quotes gumagana ang malaman na ito ay isang elementarya text. Yang na nagsasabing siya wrote it: