True or false: when the passive cannot be undone

Exercise and reference answers

Questions

1. Statement is true

   Yes

   Statement

   A passive sentence with no agent may have no unique active form.

2. Statement is true

   Yes

   Statement

   'Mistakes were made' leaves the doer unnamed.

3. Statement is true

   No

   Statement

   Every passive sentence can be turned active with certainty.

4. Statement is true

   Yes

   Statement

   Recovering the agent is the first step of the reverse change.

5. Statement is true

   Yes

   Statement

   The agent follows 'by' when it is stated.

Explanation