| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun prp] [vb past] [prep] a period [prep] | 9 |
|
| 2 | [noun prp] [vb past] [prep] a period [prep] | 9 |
|
| 3 | [noun prp] [vb past] [prep] a period of | 9 |
|
| 4 | [noun prp] [vb past] [prep] a period of | 9 |
|
