| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb -s] [prep] [art] period of | 29 |
|
| 2 | [vb -s] [prep] a period of | 19 |
|
| 3 | [vb -s] [prep] the period of | 10 |
|
| 4 | [vb -s] with [art] period of | 5 |
|
