| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a [num] year [noun] | 282 |
|
| 2 | [prep] a [num] year [noun sg] | 279 |
|
| 3 | [prep] a [num] [noun] period | 204 |
|
| 4 | [prep] a [num] [noun sg] period | 202 |
|
| 5 | [prep] [art] [num] year period | 171 |
|
| 6 | [prep] [art] [num] year period | 171 |
|
| 7 | [prep] a [num] year period | 111 |
|
| 8 | [prep] a [adj] year period | 110 |
|
| 9 | [prep] a [num] year period | 110 |
|
| 10 | [prep] a [num] year period | 110 |
|
