| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adj] a period [prep] | 19 |
|
| 2 | [adj] a period [prep] | 19 |
|
| 3 | [adj] a period of | 14 |
|
| 4 | [det] a period [prep] | 12 |
|
| 5 | such a period [prep] | 11 |
|
| 6 | such a period [prep] | 11 |
|
| 7 | [adj] a period [prep] | 5 |
|
