Somebody could exchange a sheep. A sheep could be exchanged. Change

1. People needed in more practical system. - More practical system was needed in by people. - Люди нуждались в более удобной системе.
2. Most governments now issue paper money in the form of notes. - Paper money in the form of notes is issued by most governments now. - Бумажные средства в виде банкнот выпускаются сейчас большинством правительств.
3. Filling stations will not accept cash at night. - Cash will not be accepted by filling stations at night. - Наличные средства не будут приниматься на заправочных станциях ночью.