機器
abstract
admittance
air
area
background
bank
barrier
base
battle
battleship
behind
boat
classified
close
concrete
confidential
deposit
door
entrance
entry
gate
handle
industrial
industry
iron
lock
marine
metal
navy
ocean
old
operated
porthole
protection
safe
safety
sea
secret
secure
ship
shipping
steel
storage
submarine
tight
wall
water
wheel
window