| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] been [verb] for several | 18 |
|
| 2 | had be [verb] for several | 17 |
|
| 3 | [vb past] be [v-ing] for several | 11 |
|
| 4 | [vb past] be [vb pp] for several | 7 |
|
