| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | what [verb] behind the | 36 |
|
| 2 | what lie behind the | 34 |
|
| 3 | what [vb past] behind the | 19 |
|
| 4 | what lay behind the | 18 |
|
| 5 | what [vb -s] behind the | 17 |
|
| 6 | what lies behind the | 16 |
|
