| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a [adj] period [prep] | 871 |
|
| 2 | [prep] a given [noun] [prep] | 273 |
|
| 3 | [prep] [art] given period [prep] | 19 |
|
| 4 | [prep] a given period [prep] | 18 |
|
