英文關鍵字
bond
burns
chain
connection
craftsman
danger
dirty
ditch
earthen
electrode
equipment
factory
fuel
heat
helmet
industry
iron
laborer
machine
manufacturing
mask
melting
metal
metalwork
outdoors
overalls
pipe
pipeline
pipes
power
protection
protective
safety
skill
smoke
solder
sparks
steel
suit
technology
tool
torch
traffic
trench
truck
tube
visor
weld
welder
welding
work
worker
workwear