| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a [adj] period | 2001 |
|
| 2 | [prep] a [adj] period | 2001 |
|
| 3 | over a [adj] [noun] | 1914 |
|
| 4 | over a [adj] [noun sg] | 1801 |
|
| 5 | over [art] [adj] period | 853 |
|
| 6 | over a [adj] period | 545 |
|
| 7 | over a [adj] period | 545 |
|
