| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun prp] can [be] [vb pp] back [prep] | 6 |
|
| 2 | [noun prp] can be [verb] back [prep] | 6 |
|
| 3 | [noun prp] can [be] [verb] back [prep] | 6 |
|
| 4 | [noun prp] can [be] traced back [prep] | 5 |
|
| 5 | [noun prp] can [be] trace back [prep] | 5 |
|
