| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | a [adj] period [prep] time | 319 |
|
| 2 | [adv] [adj] period [prep] time | 57 |
|
| 3 | [adv] a [adj] period [prep] | 53 |
|
| 4 | [adv] a period [prep] time | 21 |
|
