2) Letters are written every week.
3) All the milk has just been spilt (by Bob).
4) The dog was let in (by Ann).
5) Nobody is suspected.
6) The secret will be kept.
7) My sister was frightened (by me).
8) Ann will be met in the park (by Pete).
9) The pupils were told to sit down.
10) The bicycle wasn't repaired (by them).
11) The money won't be taken (by us).
12) He wasn't left alone (by them)