| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] [prep] a longer period | 19 |
|
| 2 | [vb pp] [prep] a longer period | 14 |
|
| 3 | [verb] over a longer period | 11 |
|
| 4 | [verb] over a longer period | 11 |
|
| 5 | [verb] for a longer period | 7 |
|
| 6 | [verb] for a longer period | 7 |
|
