| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] [prep] a [adj] years | 237 |
|
| 2 | [noun sg] [prep] a [adj] years | 177 |
|
| 3 | period [prep] a [adj] [noun] | 82 |
|
| 4 | period [prep] a [adj] [noun pl] | 20 |
|
| 5 | period [prep] [art] [adj] years | 12 |
|
| 6 | period [prep] a [adj] years | 8 |
|
| 7 | period [prep] a [adj] year | 8 |
|
