Ответ:

She could cook soup when she was 15.

• - She couldn't cook soop when she was 15.

• ? Could she cook soup when she was 15?

• Yes, she could. // No, she couldn't.
• Who could cook soup when she/he was 15?
• What could she cook when she was 15?
• What could she do when she was 15?
• When could she cook soup?

We visited China last summer.

• - We didn't visit China last summer.
• Did we visit China last summer?
• Yes, we did. // No, we didn't.
• Who visited China last summer?
• What did we do last summer?
• What country did we visit last summer?
• When did we visit China?

They were at the zoo at the weekend.

• - They weren't at the zoo at the weekend.
• Were they at the zoo at the weekend?
• Yes, they were. // No, they weren't.
• Who was at the zoo at the weekend? (или Who were at the zoo at the weekend)
• What did they do at the weekend?
• Where were they at the weekend?
• When were they at the zoo?

He found a golden ring in the street yesterday.

• - He didn't find a golden ring in the street yesterday.
• Did he find a golden ring in the street yesterday?
• Yes, he did. // No, he didn't.
• Who found a golden ring in the street yesterday?
• What did he find in the street yesterday?
• What ring did he find in the street yesterday?
• Where did he find a golden ring yesterday?
• When did he find a golden ring in the street?