| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] [adv] a [noun] [prep] | 8906 |
|
| 2 | [be] [adv] [art] period [prep] | 29 |
|
| 3 | [be] [adv] [art] period [prep] | 29 |
|
| 4 | [be] [adv] a period [prep] | 21 |
|
