| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | than have previously been [vb pp] | 25 |
|
| 2 | than had previously be [vb pp] | 19 |
|
| 3 | than have previously be thought | 7 |
|
| 4 | than has previously be [vb pp] | 6 |
|
