| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] [verb] [prep] a [adj] period | 76 |
|
| 2 | [be] [verb] [prep] a longer [noun sg] | 16 |
|
| 3 | [be] [verb] [prep] a longer [noun] | 16 |
|
| 4 | [be] [verb] [prep] a [adj -er] period | 15 |
|
| 5 | [be] [verb] [prep] a long period | 14 |
|
| 6 | [be] [verb] [prep] a longer period | 11 |
|
| 7 | [be] [verb] [prep] [art] longer period | 10 |
|
| 8 | [be] [verb] [prep] a longer period | 10 |
|
| 9 | [be] [verb] [prep] a longer period | 10 |
|
