Reported speech !

2. Cathy said that she had never been jet-skiing before.

( Present perfect -> past perfect )

3. Liam said he would watch the documentary with me that night.

( Will -> would и меняются маркеры времени на прошлое время )

4. George said that we couldn't go out because it was stormy.

( Present simple -> past simple, present continuous -> past continuous )

5. Harriet said that the volcano had erupted twice that year.

( Present perfect -> past perfect и меняются маркеры времени на прошлое время )

6. Chris said that he would probably study maths at college.

( Will -> would )

7. Joe said that we could visit the aquarium that day.

( Can -> Could )

8. Mandy said that a new florist's had opened in town.

( Present perfect -> past perfect )

Удачи с учёбой !!