10.3

1. Of the five events in the _, Jane is the best at swimming. centennial quintennial pentathlon quadrathlon 2. Our social studies class is studying the history of the twentieth_. decibel century centibel decury 3. Ms. Lopez thinks that she will be able to _ her earnings at her new job. centimate centuple quintuple decimate 4. The children are looking forward to the winter break, which starts in _. December octagon Centember quintagon 5. Sam found it difficult to read the map because he did not know what_they were in. quadrant pentet quintet decrant 6. The museum has an unusual octagonal room with paintings hung on all eight sides.7. Grandmother becomes an octogenarian today, and we are going to her eightieth birthday.8. The parade is a quadrennial event; if we miss it today we'll have to wait another four years.9. The quadruplets are impossible to tell apart when they wear the same clothes.10. October is Lisa's favorite month because she loves dressing up for Halloween.