| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | back [prep] the last [noun] | 29 |
|
| 2 | back [prep] the last [noun sg] | 27 |
|
| 3 | back to the last [noun] | 10 |
|
| 4 | back [prep] the last century | 6 |
|
| 5 | back [prep] the last century | 6 |
|
