英文關鍵字
abstract
architecture
background
blocks
building
bundle
cement
closeup
concrete
construct
construction
corrosion
engineering
equipment
factory
fittings
gray
grey
ground
group
heap
heavy
houses
industrial
industry
iron
lines
links
manufacturing
marking
material
metal
nobody
objects
panning
pattern
pole
power
prepare
rail
rebar
reinforcement
rods
rough
rusty
scheme
stack
steel
strength
texture
warehouse
welder
welding
wire