英文關鍵字
activity
arch
blue
bridge
bridging
building
built
business
city
column
concrete
construction
contemporary
county
crane
crossing
derrick
design
engineer
engineering
frame
highway
horizontal
industry
lapse
machine
machinery
metal
moving
multiple
occupation
orange
organization
place
planning
power
ramp
road
rod
site
sky
steel
street
structure
technician
time
transportation
work
workbench
worker
working