Their chief failing was that with such a limited command vector, the hierarchies became quite deep.

它们最失败的地方是尽管命令数量有限, 但也必须深入到各级菜单.

Their chief failing was that with such a limited command vector, the hierarchies became quite deep .

它们最失败的地方是尽管命令数量有限，但也必须深入到各级菜单。