| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb pp] [verb] at | 1277 |
|
| 2 | [vb pp] [to-vb] at | 1030 |
|
| 3 | [vb pp] to operate [prep] | 123 |
|
| 4 | [vb pp] to operate [prep] | 123 |
|
| 5 | [verb] to operate at | 28 |
|
| 6 | [vb pp] operate at | 19 |
|
| 7 | [vb pp] to operate at | 16 |
|
