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1/
1. Volunteering is special to many people because they can help others.
2. Although he tried hard, he couldn't set up a new world record.
3. They went for a picnic and we went grass sliding.
4. The TV set did not work properly, so I turned it off.
5. Volunteer work is very hard for teenagers in the city, but they enjoy doing it.
2/
1. The seats at the Opera House are very comfortable.
2. Kien was chosen for the school's football team two years ago.
3. If you are not careful, you'll hurt yourself.
4. Jane is interested in collecting dolls from foreign countries.
5. Because of the heavy rain, they didn't go camping yesterday.