它的意思是：
级别,层数
No.= number
levels 层次,级别
This puzzle attracts people on a number of levels.
七巧板吸引了各个阶层的人们.
But reusability comes at a number of levels.
但是可重用性具有许多级别.
祝进步,
它的意思是：
级别,层数
No.= number
levels 层次,级别
This puzzle attracts people on a number of levels.
七巧板吸引了各个阶层的人们.
But reusability comes at a number of levels.
但是可重用性具有许多级别.
祝进步,