| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | a [adj] period of | 842 |
|
| 2 | [vb base] a [adj] of | 73 |
|
| 3 | [vb base] a period of | 35 |
|
| 4 | [vb base] a [adj] period | 34 |
|
