| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] three year [unc] duration | 25 |
|
| 2 | of three year [unc] duration | 25 |
|
| 3 | of three year [unc] duration | 25 |
|
| 4 | [prep] three year [unc] duration | 25 |
|
