What are the advantages and disadvantages of cleaners, doctors and welders?

Cleaners get up early and can breathe fresh air, sweeping the floor every day can be used as exercise, doctors have a variety of benefits, wages are very good, physical strength is not so tired, welders really did not find any good.

These are the advantages, disadvantages, if the cleaner every day to eat a lot of ash on the road, to get up very early, every day on the road is also easy to get into car accidents, the wages are also very low, the doctor will sometimes be patients or medical equipment infected with disease, the heart of the pressure, the soldering summer sweating, hot, long those sparks on the eyes is also damage, squatting too long and also susceptible to some of the disease.