| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun prp] have been working [prep] a | 11 |
|
| 2 | [noun prp] had been working [prep] a | 5 |
|
| 3 | [noun prp] have been working on a | 5 |
|
| 4 | [noun prp] have been working on a | 5 |
|
