| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] be working on | 54 |
|
| 2 | [vb past] [been] working on | 53 |
|
| 3 | [vb past] been working on | 53 |
|
| 4 | had [be] working on | 46 |
|
| 5 | 'd [be] working on | 7 |
|
