Question: how to use mview in autocad?
Answer: Corner of viewport, opposite corner. Specifies the first corner of a rectangular viewport followed by a diagonal corner.
On. Makes a selected viewport active. ... 
Off. Makes a selected viewport inactive. ... 
Fit. Creates one viewport that fills the layout to the edges of the printable area. ... 
Shadeplot. ... 
Lock. ... 
Object. ... 
Polygonal.