| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a [adj] period of [noun sg] | 121 |
|
| 2 | over a [adj] period of time | 120 |
|
| 3 | over a [adj] period of time | 120 |
|
| 4 | over a [adj] period of [noun] | 119 |
|
| 5 | over a long period of [noun] | 81 |
|
| 6 | over a long period of [noun] | 75 |
|
| 7 | over a short period of [noun] | 8 |
|
| 8 | over a prolonged period of [noun] | 7 |
|
| 9 | over a considerable period of [noun] | 7 |
|
| 10 | over a considerable period of [noun] | 7 |
|
| 11 | over a prolonged period of [noun] | 7 |
|
| 12 | over a [adj -er] period of [noun] | 7 |
|
| 13 | over a short period of [noun] | 7 |
|
| 14 | over a longer period of [noun] | 6 |
|
| 15 | over a [adj] period of years | 5 |
|
| 16 | over a given period of [noun] | 5 |
|
| 17 | over a [adj] period of [noun pl] | 5 |
|
| 18 | over a given period of [noun] | 5 |
|
| 19 | over a [adj] period of year | 5 |
|
