英文關鍵字
acetylene
butane
car
construction
cutting
device
duty
engineering
equipment
factory
fire
flame
gas
heat
heavy
ignition
industrial
industry
iron
labor
manufacturing
mechanic
mechanical
metal
molten
natural
occupation
oxygen
part
production
propane
skill
spark
spatter
steel
structure
technician
tool
torch
welder
welding
work
worker
working
workman