1. Active: They are cleaning (cleaning) the classrooms now. Passive: The classrooms are being cleaned now. 2. Active

The correct passive forms of the given sentences are as follows:

1. Active: They are cleaning the classrooms now.
Passive: The classrooms are being cleaned now.

In this sentence, the subject "the classrooms" becomes the object in the passive voice, and the verb "cleaned" is changed to the present continuous form "are being cleaned" to indicate an ongoing action.

2. Active: They are repairing the road at the moment.
Passive: The road is being repaired at the moment.

The subject "the road" becomes the object in the passive voice, and the verb "repaired" is changed to the present continuous form "is being repaired" to indicate an ongoing action.

3. Active: The teacher is marking the tests.
Passive: The tests are being marked.

Here, the subject "the tests" becomes the object in the passive voice, and the verb "marked" is changed to the present continuous form "are being marked" to indicate an ongoing action.

4. Active: They are not using the computer.
Passive: The computer is not being used.

In this sentence, the subject "the computer" becomes the object in the passive voice, and the verb "used" is changed to the present continuous form "is not being used" to indicate that the action is not happening.

5. Active: He is doing the washing-up.
Passive: The washing-up is being done.

Here, the subject "the washing-up" becomes the object in the passive voice, and the verb "done" is used to indicate the action being performed.

6. Active: They are repairing the roof.
Passive: The roof is being repaired.

The subject "the roof" becomes the object in the passive voice, and the verb "repaired" is changed to the present continuous form "is being repaired" to indicate an ongoing action.

It seems that there is an incomplete sentence given in the request. Please provide the complete sentence so I can assist you further with the seventh sentence.