AutoCAD Modify Tools Move, Copy , Object Selection and Mirror etc.

Modify command is used on daily basis we can change existing objects or to use existing objects to create new and similar objects. 
Perform editing operations such as erase, move, rotate and trim on the objects in a drawing.

The modify commands listed below are covered in this topic.
Erase
Copy
Move
Rotate
Trim
Scale
Mirror
Array
Stretch
Extend
Fillet
Chamfer
Offset
Explode 

 1.  ERASE   
The erase command deletes the objects you select from the drawing. Any of the object
selection methods can be used to highlight the object to erase short cut key “E” . The only other required
action is press Enter to cause the erase to take effect.

Select the object > E (shortcut command) & spacebar > enter or spacebar 
                           

Note: If objects are erased accidentally, Ctrl+Z or Undo command can be used immediately following
the mistake to undo one step, or oops can be used to bring back into the drawing
whatever was erased the last time erase was used.          

2. Trim and Extend
Trimming and extending are some of the most commonly used operations.
The Trim command allows  to trim ( shorten ) the end of end object back
to the intersection of another object . The middle section of an object can
also be trimmed between two intersection objects sort cut key “TR”. There are two steps to this
command;
1. PICK one or more “cutting edge” ( existing object )
2. Then PICK the object or objects to trim ( portion to remove )
Select the object > TR (shortcut command) & spacebar > enter or space button> trim the object  by clicking mouse 

 You want to Extend the lines that represent the steps for this deck. You start the Extend command, select the boundary, and then press Enter or the Spacebar.
Select the primary object  > EX (shortcut command) & spacebar > Select the second line>Spacebar

3. Copy 
The copy command allows  to copy the object one or more time, short cut command key CO Or CP.

Select the object > CO or CP(shortcut command) & spacebar > Pick the object point > Specify the distance for new object > enter or space button

                                       
4. Move 
Move allows  to relocate one or more objects from the existing position in the
drawing to any other position you specify. After selecting the objects to move, you must
specify the base point and second point of displacement.
Select the object > M(shortcut command) & spacebar > Pick the object point > Specify the distance for  object > enter or spacebar

5.OFFSET
Offset creates a parallel copy of selected object. Selected object can be Lines, Arcs,
Circles, Plines or other objects. Two options are available with offset; offset a specified
distance and offset through a specified point.
Select the object > O(shortcut command) & spacebar > Pick the object point > Specify the distance > enter or spacebar
                                     
6. Mirror
This command creates a mirror image of selected existing objects. You can retain or delete
the original objects ( ‘old object’ ). After selecting objects, you create two points specifying
a ‘mirror line’, about which to mirror.
Select the object > MI(shortcut command) & spacebar > Specify object first base point > Specify object second base point >enter or spacebar
                       
7. Array
The array command creates either a Rectangular or Polar ( circular ) pattern of
existing object that you select. The pattern could be created from a single or from a group
of objects. Array copies a duplicate set of objects for each ‘item’ in the array.
Select the object > AR(shortcut command) & spacebar > Specify Rectangular Array > Specify Columns, Rows and distance between two object >enter or spacebar
                                                   
Select the object > AR(shortcut command) & spacebar > Specify Polar Array > Specify center point >enter or spacebar
                                                     
8. Stretch
  Object can be made longer or shorter with STRETCH. When ‘Stretched’, Line become longer or shorter       Circle do not stretch; rather, they move if the circle is selected within the Crossing Window .
  Select the object (Crossing selection)> S(shortcut command) & spacebar>  Specify base point or Distance> Specify second point  >drop the point by mouse
                                               

9.  Scale
The scale command is used to increase or decrease the size of objects in a drawing.
We perform the scaling two type.
 1. Scale Factor
 2. Reference 

1. Scale Factor:
Select the object to scale> SC(shortcut command) & spacebar>  Specify base point > Enter the scale factor or drag and click to specify a new scale
                                                             
 2. Reference:
Select the object to scale> SC(shortcut command) & spacebar>  Specify base point > Enter r (Reference)>Select the first and second reference points, or enter a value for the reference length
                                                             

9. FILLET
A fillet or round can be inserted at a single vertex.
F(shortcut command) & spacebar>  Specify Radius value > Select the first line >Select the Second line.                                           
  10. Chamfer
  Chamfer is a manufacturing process used to replace a sharp corner with an angled surface.  
  CHA(shortcut command) & spacebar>  Specify First Distance > Specify Second Distance >Select the      Trim > Select First line > Select Second line >Spacebar.

                               
 11. Explode
  Explodes a compound object when you want to modify its components separately or break.
X(shortcut command) & spacebar>  Select the object >Spacebar.
                                                     
    12. Rotate
    Selected object can be rotated to any position with this command. After selecting
    object to rotate, you select a “basepoint” then specify an angle for rotation.     
   RO(shortcut command) & Spacebar>  Select the object & Spacebar>Specify Base Point > Give the         Angle or Rotate by Mouse >  Spacebar.