| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | has been shown [prep] | 211 |
|
| 2 | [vb -s] been shown to | 109 |
|
| 3 | [vb -s] been shown in | 49 |
|
| 4 | [vb -s] been shown by | 30 |
|
