| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] have [been] [vb pp] at a | 8 |
|
| 2 | [modal v] have [been] [vb pp] at a | 8 |
|
| 3 | have [been] [vb pp] at a [noun sg] | 5 |
|
| 4 | have [been] [vb pp] at a [noun] | 5 |
|
