機器
armed
belt
building
bulldoze
bulldozer
caterpillar
constructing
construction
dirth
dirty
earth
equipment
farm
floor
forces
grass
ground
heavy
history
iron
machinery
metal
military
mode
mud
muddy
old
part
peace
road
roads
russia
rust
steel
strong
tank
technology
track
tracks
tractor
transport
transportation
tread
troops
vehicle
vehicles
war
wheel
work