英文關鍵字
roof
temporary
building
fence
construction
scaffolding
work
industry
site
industrial
equipment
structure
engineering
steel
scaffold
architecture
safety
occupation
worker
development
business
background
high
facade
frame
people
tower
maintenance
concrete
metal
platform
outdoors
helmet
nobody
workman
material
portable
risk
planks
adjustable
group
activity
tool
men
wall
inspection
outdoor
job
house
build
repair
housing
diagonal