| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be [vb pp] over a [adj] period | 21 |
|
| 2 | [be] [vb pp] over a [adj] period | 11 |
|
| 3 | [be] [vb pp] over a [adj -er] period | 10 |
|
| 4 | [be] [vb pp] over a long period | 10 |
|
| 5 | [be] [vb pp] over a longer period | 8 |
|
