| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb pp] [prep] a long period | 67 |
|
| 2 | [adv] [vb pp] [prep] a long | 56 |
|
| 3 | [adv] [prep] a long period | 36 |
|
| 4 | [adv] [vb pp] [prep] a period | 35 |
|
