Question

The door bell while- (ring) she was reading​

Answer 1

Answer:

She was reading while the door bell was/is ringing

Answer 2

Answer:

The doorbell rang while she was reading.

Explanation:

In the sentence,

The doorbell rang while she was reading.

ring will be converted into simple past tense.

We use 'rang' as the action was done in the past.

The verb 'rang' is in the simple past tense.

For example-

1. I went for a long walk.
2. We drank milk for breakfast.

The verbs in the sentences are in simple past tense because all the actions were completed in the past.