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