| one | 1.______ | eleven | 11.______ |
| two | 2.______ | twelve | 12.______ |
| three | 3.______ | thirteen | 13.______ |
| four | 4.______ | fourteen | 14.______ |
| five | 5.______ | fifteen | 15.______ |
| six | 6.______ | sixteen | 16.______ |
| seven | 7.______ | seventeen | 17.______ |
| eight | 8.______ | eighteen | 18.______ |
| nine | 9.______ | nineteen | 19.______ |
| ten | 10.______ | twenty | 20.______ |
| The _________ question is much more difficult than this one. | |||
| [ ] | |||
| A. sixth B. six C. sixteen D. sixty | |||
| 填入适当的序数词。 | |||
| 1. September the__________ month of a year 2. May the__________ month of a year 3. February the__________ month of a year 4. January the__________ month of a year 5. November the__________ month of a year 6. June the__________ month of a year | |||
| 写出下列序数词。 | |||