| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | the [noun sg] [prep] a long period | 17 |
|
| 2 | the [noun sg] of a long period | 9 |
|
| 3 | the [noun sg] for a long period | 7 |
|
| 4 | the [noun sg] over a long period | 5 |
|
