abstract
background
bomb
choice
color
concept
construction
cut
cutter
cutting
danger
decision
electrician
electricity
equipment
finger
hand
home
house
idea
instrument
isolated
line
man
mesh
metal
mine
occupation
person
plier
pliers
police
power
red
repair
safety
security
select
sign
solution
symbol
technician
technology
terrorism
tool
white
wire
work
worker