| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] been under surveillance | 7 |
|
| 2 | had been under surveillance | 7 |
|
| 3 | [vb past] been under surveillance | 7 |
|
| 4 | have been under surveillance | 7 |
|
| 5 | been under surveillance [prep] | 6 |
|
| 6 | been under surveillance [prep] | 6 |
|
