FormObject + To be + past participle
Tense
Present simple, past simple, present perfect and future.
is/are was have/has is going to
When do we use it?
-When who did the action is not known, or is not important.
-use 'by' at the end of the passive sentence if you want to include who did the action.
The phone was invented in 1875.
The phone was invented in 1875 by Alexander Bell.