do business (?.)
- barter
- be employed
- buy and sell
- carry on business
- change
- deal
- exchange
- follow a trade
- give in exchange
- have a job
- horse-trade
- interchange
- keep up
- labor
- moonlight
- practice a profession
- set up shop
- stay employed
- swap
- swap horses
- switch
- take in exchange
- toil
- trade
- trade in
- trade off
- trade sight unseen
- traffic
- transact business
- truck
- work
- work at
- work for