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