| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | of [noun sg] [prep] a long period | 16 |
|
| 2 | of [noun sg] [prep] a long period | 15 |
|
| 3 | of [noun sg] over a long period | 12 |
|
| 4 | of [noun sg] over a long period | 12 |
|
