by Liz Walter
Look at these two sentences:
My sister made the cake.
The cake was made by my sister.
Both these sentences mean the same. The first is an active sentence: it tells you what the sister did. The second is a passive sentence: it tells you what happened to the cake.
Here are some more passive sentences. Note that we use by before the person or thing that does something, and with before the thing that is used to do it:
‘Hamlet’ was written by Shakespeare.
The pieces of wood were cut by a machine.
The rope was cut with a sharp knife.