| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a [adj] period of | 137 |
|
| 2 | over a [adj] period of | 128 |
|
| 3 | [prep] a prolonged period of | 18 |
|
| 4 | [prep] a prolonged period of | 18 |
|
| 5 | over a prolonged period [prep] | 9 |
|
| 6 | over a prolonged period [prep] | 9 |
|
| 7 | over a prolonged [noun] of | 8 |
|
| 8 | over a prolonged period of | 8 |
|
| 9 | over [art] prolonged period of | 8 |
|
| 10 | over a prolonged period of | 8 |
|
| 11 | over a prolonged period of | 8 |
|
| 12 | over [art] prolonged period of | 8 |
|
| 13 | over a prolonged period of | 8 |
|
