| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a [adj] period [prep] | 773 |
|
| 2 | [prep] a [adj] period [prep] | 736 |
|
| 3 | [prep] a [adj] period of | 544 |
|
| 4 | for a [adj] period [prep] | 272 |
|
| 5 | for a [adj] period [prep] | 272 |
|
| 6 | [prep] a long period [prep] | 179 |
|
| 7 | over a [adj] period [prep] | 176 |
|
| 8 | over a [adj] period [prep] | 176 |
|
| 9 | [prep] a long period [prep] | 162 |
|
| 10 | [prep] a short period [prep] | 97 |
|
| 11 | [prep] a short period [prep] | 91 |
|
| 12 | after a [adj] period [prep] | 80 |
|
| 13 | after a [adj] period [prep] | 80 |
|
| 14 | [prep] a [adj] period in | 72 |
|
| 15 | of a [adj] period [prep] | 41 |
|
| 16 | of a [adj] period [prep] | 41 |
|
| 17 | within a [adj] period [prep] | 40 |
|
| 18 | within a [adj] period [prep] | 40 |
|
| 19 | [prep] a brief period [prep] | 36 |
|
| 20 | [prep] a [adj -er] period [prep] | 36 |
|
| 21 | [prep] a brief period [prep] | 36 |
|
| 22 | in a [adj] period [prep] | 30 |
|
| 23 | in a [adj] period [prep] | 30 |
|
| 24 | [prep] a fixed period [prep] | 29 |
|
| 25 | [prep] a fixed period [prep] | 29 |
|
| 26 | during a [adj] period [prep] | 25 |
|
| 27 | during a [adj] period [prep] | 25 |
|
| 28 | [prep] a certain period [prep] | 22 |
|
| 29 | [prep] a certain period [prep] | 22 |
|
| 30 | [prep] a limited period [prep] | 21 |
|
