| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a [adj] period of [noun] | 126 |
|
| 2 | over a long period of [noun] | 81 |
|
| 3 | [prep] a longer period of [noun] | 11 |
|
| 4 | over a [adj -er] period of [noun] | 7 |
|
| 5 | over a longer period of [noun] | 6 |
|
| 6 | over a longer [noun] of [noun] | 6 |
|
| 7 | over a longer period of [noun] | 6 |
|
| 8 | over [art] longer period of [noun] | 6 |
|
| 9 | over a longer period [prep] [noun] | 6 |
|
| 10 | over [art] longer period of [noun] | 6 |
|
| 11 | over a longer [noun sg] of [noun] | 6 |
|
