| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | been [vb pp] by a period [prep] | 6 |
|
| 2 | been [vb pp] by a period of | 6 |
|
| 3 | been [vb pp] by a period [prep] | 6 |
|
| 4 | been [vb pp] by a period of | 6 |
|
