| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | and over a period of [noun] | 9 |
|
| 2 | and over a period [prep] [noun] | 9 |
|
| 3 | and over a period of [noun] | 9 |
|
| 4 | and over a period [prep] [noun sg] | 8 |
|
| 5 | and over a period [prep] time | 7 |
|
| 6 | and over a period [prep] time | 7 |
|
