| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it be [pos pn] duty to | 8 |
|
| 2 | it be [pos pn] duty to | 8 |
|
| 3 | it be [pos pn] duty to | 8 |
|
| 4 | it was [pos pn] duty to | 5 |
|
