| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a period of about [adj] | 25 |
|
| 2 | over a period of [adv] [adj] | 25 |
|
| 3 | [prep] a period of about [adj] | 25 |
|
| 4 | over a [noun sg] of about [adj] | 14 |
|
| 5 | over a [noun] of about [adj] | 14 |
|
| 6 | over [art] period of about [adj] | 13 |
|
| 7 | over [art] period of about [adj] | 13 |
|
| 8 | over a period of about [adj] | 12 |
|
| 9 | over a period of about [adj] | 12 |
|
| 10 | over a period [prep] about [adj] | 12 |
|
| 11 | over a period of about [adj] | 12 |
|
