| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a period [prep] a [noun] | 15 |
|
| 2 | [prep] a period [prep] a year | 9 |
|
| 3 | [prep] a period [prep] a year | 9 |
|
| 4 | over [art] period [prep] a year | 6 |
|
| 5 | over [art] period [prep] a year | 6 |
|
| 6 | over a period [prep] [art] year | 5 |
|
| 7 | over a period [prep] a year | 5 |
|
| 8 | over a [noun] [prep] a year | 5 |
|
| 9 | over a period [prep] a year | 5 |
|
| 10 | over a period [prep] a year | 5 |
|
| 11 | over a [noun sg] [prep] a year | 5 |
|
| 12 | over a period [prep] a year | 5 |
|
