| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [adv] a [adj] period | 27 |
|
| 2 | [prep] [adv] a [adj] period | 27 |
|
| 3 | [prep] only a [adj] period | 17 |
|
| 4 | for [adv] a [adj] period | 17 |
|
| 5 | [prep] only a [adj] period | 17 |
|
| 6 | [prep] [adv] a short period | 11 |
|
| 7 | [prep] [adv] a short period | 11 |
|
| 8 | [prep] quite a [adj] period | 8 |
|
| 9 | [prep] quite a [adj] period | 8 |
|
| 10 | [prep] [adv] a long period | 6 |
|
| 11 | [prep] [adv] a long period | 6 |
|
