| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have existed for a [adj] | 7 |
|
| 2 | [verb] existed for a [adj] | 7 |
|
| 3 | existed for a [adj] [noun] | 7 |
|
| 4 | existed for a [adj] [noun sg] | 7 |
|
| 5 | existed for a [adj] time | 5 |
|
| 6 | existed for a [adj] time | 5 |
|
