| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] have been [adj] year | 30 |
|
| 2 | [modal v] have been [adj] years | 28 |
|
| 3 | [modal v] have been [num] year | 22 |
|
| 4 | would have been [adj] year | 17 |
|
| 5 | would have been [adj] year | 15 |
|
| 6 | may have been [adj] year | 5 |
|
| 7 | may have been [adj] year | 5 |
|
