| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] [adv] a period [prep] | 68 |
|
| 2 | [verb] [adv] a long period | 29 |
|
| 3 | [verb] a long period [prep] | 19 |
|
| 4 | [adv] a long period [prep] | 13 |
|
