input in command line with Keyboard AutoCAD tools names
l draw line
pl draw poly line
c draw circle
rec draw rectangle
a draw arc
z, then a zoom view, and zoom all
e erase
co

copy

m move
o offset
tr trim
ro rotate
ltscle change line style scle
pedit edit a polyline, such as join, close, pline curve
s stretch your selection
sc scale
d change dimension settings
h hatch
ucs change user coordination system
ctrl+z undo
hold middle wheel pan view
roll middle wheel zoom view

ex

extend
rotate3d rotate in 3D world
surftab1 change the subdivision of surface model
box create a 3D cube
extrude extrude a regioned face to 3D s
use "P" to extrude along a path
region convert a closed wireframe geometry to a solid face.
revolve rotate a 2D profile to generate a 3D form
union union two solid objects into one
subtract / su subtract one solid object from another