. no one in the group is younger than Mai
=> Mai is the tallest in the group
2. it takes Minh 2 hour to do his homework every day
=> Minh spends 2 hours doing his homework everyday
3. we spent 2 hour watering the flowers every day
=> it takes us 2 hours to water the flowers every day
4. it took Nam an hour a day to practice the piano
=> Nam spents an hour a day practicing the piano
5. it takes Tom 3 hour to do his homework very day
=> Tom spends 3 hours doing his homework every day