Написать по 3 примера(past continious,past perfect,,past simple)

Active Voice:
1. Past simple. I sold cars
    Past perfect. I had sold cars
    Past continuous. I was selling cars
Active Voice:
2. past simple. I signed the contract
    past perfect. I had signed the contract
    past continuous. I was signing the contract
Active Voice:
3. past simple. We calculated the transaction costs
   past perfect. We had already calculated the transaction costs
   past continuous. We were calculating the transaction costs