| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have been [vb pp] over the last | 25 |
|
| 2 | have been [vb pp] over the [num ord] | 13 |
|
| 3 | has been [vb pp] over the [num ord] | 10 |
|
| 4 | have been developed over the [num ord] | 5 |
|
