| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb pp] for a period [prep] | 45 |
|
| 2 | for a long period [prep] | 33 |
|
| 3 | [vb pp] for a long period | 14 |
|
| 4 | [vb pp] a long period [prep] | 9 |
|
