关于js多维数组的问题

Question

比如一个多维数组
[["A","B","C"],[1,2,3],["X","Y","Z"],[7,8,9]];

            如果我想在"A","B","C"后面加个D，该怎么写？
            push是添加在数组最后， 不太适用

          本人小白，求教

            希望能有个最简单的方法

Answer 1

var array = [["A","B","C"],[1,2,3],["X","Y","Z"],[7,8,9]];
array[0].push("D");