| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have been operating a | 6 |
|
| 2 | [verb] been operating a | 6 |
|
| 3 | been operating [prep] a | 7 |
|
| 4 | been operating [prep] a | 7 |
|
| 5 | been operating a [noun] | 5 |
|
