亲爱的朋友您好，很高兴为您解答:

K12或K-12，是kindergarten through twelfth grade的简写，是指从幼儿园（Kindergarten，通常5-6岁）到十二年级（grade 12，通常17-18岁），这两个年纪是美国、澳大利亚及English Canada的免费教育头尾的两个年纪，此外也可用作对基础教育阶段的通称。

Kay through 12 或 Kay 12。

K12的英文发音Kay through 12 或 Kay 12。

K12的英文解释

K-12 is the North American designation for primary and secondary education. The expression is a shortening of Kindergarten through 12th grade,the first and last grades of free education in the United States and English Canada.