bolt
calculation
complex
complicate
conveyor
dirty
drying plant
dust
engineer
engineering
factory
gold
industry
iron
itchy
knot
knowledge
light
maintainace
metal
motor
new
nut
old
operator
paddy
plant
rice mill
ring
rotate
screw
silo
skill
steel
steel rails
strength
strong
structure
useable
useful
vintage
washer
worker