| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [num] years ' [noun] | 1138 |
|
| 2 | [num] [noun] ' duration | 95 |
|
| 3 | [num] [noun pl] ' duration | 95 |
|
| 4 | [adj] years ' duration | 71 |
|
| 5 | [num] years ['s] duration | 70 |
|
| 6 | [num] years ' duration | 70 |
|
| 7 | [num] year ' duration | 70 |
|
| 8 | [num] years [unc] duration | 70 |
|
