Concept:
In voice transformation, an active sentence is converted into passive voice by making the object of the active sentence the subject of the passive sentence. The tense of the sentence must remain the same.
For present continuous tense, the passive structure is:
\[
\text{Object} + \text{is/am/are being} + \text{past participle} + \text{by Subject}
\]
Step 1: Identify subject, verb, and object.
Subject: The teacher
Verb: is correcting (present continuous tense)
Object: the notebooks
Step 2: Make the object the subject.
"The notebooks" becomes the new subject.
Step 3: Convert the verb into passive form.
"Is correcting" becomes "are being corrected" (since "notebooks" is plural).
Step 4: Add the agent (doer).
Add "by the teacher" at the end.
Final Sentence:
The notebooks are being corrected by the teacher.