Turn the sentences from passive to active voice. 

Ερώτηση 1 / 1 (Συμπλήρωση Κενών (Χαλαρή Ταυτοποίηση) — 10 βαθμοί) 

Turn from passive to active

The cake was baked by Sarah. A new bridge was built by the construction workers. The book was written by a famous author. The emails were sent by the manager. The project has been completed by the team on time. The window had been broken by the children. The invitations were being delivered by the mailman. The problem must be solved by the engineer. The song is being sung by the choir. The homework will be done by the students before class.