ĐÂY LÀ BÀI TUẦN NÀY !
It is simply this. That Space, as our _____ (MATH) have it, is spoken of as having three dimensions, which one may call _____ (LONG), Breadth, and _____ (THICK), and is always definable by _____ (REFER) to three planes, each at right angles to the others. But some philosophical people have been asking why THREE dimensions _____ (PARTICULAR) - why not another direction at right angles to the other three?--and have even tried to construct a Four-Dimension geometry. Professor Simon Newcomb was expounding this to the New York Mathematical Society only a month or so ago. You know how on a flat surface, which has only two dimensions, we can represent a figure of a three _____ (DIMENSION) solid, and _____ (SIMILAR) they think that by models of thee dimensions they could represent one of four--if they could master the _____ (PERCEIVE) of the thing. See?'