| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | for [adj] period | 736 |
|
| 2 | for [adj] period | 492 |
|
| 3 | for prolonged [noun] | 23 |
|
| 4 | [prep] prolonged period | 22 |
|
| 5 | [prep] prolonged period | 22 |
|
| 6 | for prolonged period | 12 |
|
| 7 | for prolonged period | 12 |
|
