機器
20s
40s
50s
apprentice
apprenticeship
busy
caucasian
engineer
engineering
equipment
factory
fifties
forties
horizontal
indoors
industry
learning
machinery
male
man
manual worker
manufacturing
men
occupation
operating
overalls
people
person
precision
skilled
staff
teaching
team
three people
together
trainee
training
twenties
working
workman
workshop