Question

9. Se heard a very strange sound when de were sleeping. (Negative)
10. They aren't traveling to Germany at this momenty. (Affirmative)
11. Gustavo swims very fast at this championship. (Negative)

Answer 1

9. Se doesn't heard a very strange sound when de were sleeping.
10. They are traveling to Germany at this momenty.
11. Gustavo doesn't swim very fast at this championship.