| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it has been [vb pp] for | 100 |
|
| 2 | it [vb -s] been known for | 31 |
|
| 3 | it 's been [vb pp] for | 23 |
|
| 4 | it [vb -s] been used for | 9 |
|
