Zi ran ke jiao xue yan jiu/ Ti yu ke jiao xue yan jiu/ Yin le ke jiao xue yan jiu/ Shu xue ke jiao xue yan jiu/ Guo yu wen jiao xue yan jiu/ Li fa yu yan xue yan jiu/ Zi xun jiao yu yan jiu/ Zi ran ke jiao xue yan jiu yu shi xi/ You er shi zi jiao xue yan jiu/ Zhi ye jiao yu yan jiu/