| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] back on a [noun] | 27 |
|
| 2 | [verb] back on a [noun sg] | 23 |
|
| 3 | [vb pp] back on a [noun] | 7 |
|
| 4 | look back on a [noun] | 6 |
|
