| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be referred to | 424 |
|
| 2 | is referred to | 304 |
|
| 3 | are referred to | 273 |
|
| 4 | been referred to | 159 |
|
| 5 | was referred to | 151 |
|
| 6 | were referred to | 97 |
|
| 7 | being referred to | 68 |
|
| 8 | be referred to | 19 |
|
