| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | back up by the [noun sg] | 22 |
|
| 2 | backed up by the [noun] | 18 |
|
| 3 | backed up by the [noun] | 12 |
|
| 4 | back up by the [noun pl] | 6 |
|
