| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | has [vb pp] [prep] a period | 10 |
|
| 2 | have [vb pp] over a period | 7 |
|
| 3 | have [vb pp] through a period | 5 |
|
| 4 | have [vb pp] for a period | 5 |
|
