| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be [vb pp] over a period of | 40 |
|
| 2 | [be] [vb pp] over a period of | 40 |
|
| 3 | be [vb pp] over a period of | 15 |
|
| 4 | [was/were] [vb pp] over a period of | 15 |
|
| 5 | [be] [vb pp] over a period of | 15 |
|
| 6 | was [vb pp] over a period of | 11 |
|
| 7 | [adv] [vb pp] over a period of | 8 |
|
| 8 | [noun] [vb pp] over a period of | 8 |
|
| 9 | [adv] [vb pp] over a period of | 8 |
|
| 10 | [verb] [vb pp] over a period of | 7 |
|
| 11 | [noun pl] [vb pp] over a period of | 7 |
|
| 12 | have [vb pp] over a period of | 6 |
|
| 13 | [vb pp] [adv] over a period of | 16 |
|
| 14 | [vb pp] [adv prt] over a period of | 12 |
|
| 15 | [vb pp] over a [adj] period of | 23 |
|
| 16 | [vb pp] over a [adj] period of | 21 |
|
| 17 | [vb pp] over a long period of | 14 |
|
| 18 | [vb pp] over a long period of | 12 |
|
| 19 | [vb pp] over a period of [noun] | 31 |
|
| 20 | [vb pp] over a period of [adj] | 30 |
|
| 21 | [vb pp] over a period of [num] | 24 |
|
| 22 | [vb pp] over a period of time | 21 |
|
| 23 | [vb pp] over a period of time | 21 |
|
| 24 | [vb pp] over a period of [noun sg] | 21 |
|
| 25 | [vb pp] over a period of [noun pl] | 10 |
|
| 26 | [vb pp] over a period of years | 9 |
|
| 27 | [vb pp] over a period of year | 9 |
|
| 28 | [vb pp] over a period of [adv] | 6 |
|
| 29 | [vb pp] over a period of [adv] | 6 |
|
| 30 | [vb pp] over a period of two | 5 |
|
