| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | which has [adv] be [vb pp] to | 21 |
|
| 2 | which [vb -s] [adv] been [vb pp] to | 21 |
|
| 3 | which [vb -s] already be [vb pp] to | 7 |
|
| 4 | which [vb -s] [adv] be referred to | 5 |
|
