英文關鍵字
ancient
antique
axle
device
energy
engine
engineering
equipment
farm
farming
flow
gear
historic
industrial
industry
iron
machine
machinery
mechanical
mechanism
metal
mill
motion
old
outdoor
power
pump
retro
rotate
rotation
round
rural
rustic
smart
speed
spin
splash
technology
tool
traditional
turbine
turning
vintage
water
watermill
waterwheel
wheel
wooden
work