| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [det] [noun] [prep] a [adj] period | 40 |
|
| 2 | [det] [noun sg] [prep] a [adj] period | 23 |
|
| 3 | [det] [noun pl] [prep] a [adj] period | 15 |
|
| 4 | [det] [prep] a [adj] period [prep] | 8 |
|
| 5 | [det] [prep] a [adj] period [prep] | 8 |
|
| 6 | [det] [prep] a [adj] period of | 6 |
|
| 7 | [det] [prep] a [adj] period of | 6 |
|
