| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a [adj] period [prep] | 736 |
|
| 2 | [prep] a [adj] period [conj] | 104 |
|
| 3 | [prep] a [adj] [conj] [prep] | 53 |
|
| 4 | a [adj] period [conj] [prep] | 21 |
|
| 5 | [prep] a period [conj] [prep] | 6 |
|
