| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | has [been] working [prep] a | 12 |
|
| 2 | has been working [prep] a | 12 |
|
| 3 | has [been] working on a | 7 |
|
| 4 | has [been] working on a | 7 |
|
