| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] been [vb pp] to be [adj] | 24 |
|
| 2 | had [been] [vb pp] to be [adj] | 22 |
|
| 3 | [vb past] [been] shown to be [adj] | 6 |
|
| 4 | [vb past] [been] found to be [adj] | 5 |
|
