| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a long period | 181 |
|
| 2 | for a long period | 71 |
|
| 3 | after a long period | 22 |
|
| 4 | of a long period | 10 |
|
| 5 | from a long period | 5 |
|
| 6 | to a long period | 5 |
|
