| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] [prep] a long period | 36 |
|
| 2 | [adv] [prep] a long period | 29 |
|
| 3 | [adv] [prep] a long period | 25 |
|
| 4 | [adv] over a long period | 22 |
|
| 5 | [adv prt] [prep] a long period | 11 |
|
| 6 | [adv] [prep] a longer period | 7 |
|
| 7 | [adv] for a long period | 7 |
|
| 8 | on [prep] a long period | 5 |
|
| 9 | on [prep] a long period | 5 |
|
