| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | there have [been] a [adj] | 1007 |
|
| 2 | years there have [been] a | 70 |
|
| 3 | years there have [been] [adj] | 31 |
|
| 4 | years have [been] a [adj] | 8 |
|
