| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a [num] [noun] [prep] | 835 |
|
| 2 | [prep] a [num] [noun] period | 204 |
|
| 3 | a [num] [noun] period [prep] | 48 |
|
| 4 | [prep] a [noun] period [prep] | 46 |
|
