| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a period [prep] | 1753 |
|
| 2 | [noun] [prep] a period | 832 |
|
| 3 | [noun] [prep] a [prep] | 115 |
|
| 4 | [noun] a period [prep] | 18 |
|
| 5 | [noun] [prep] period [prep] | 17 |
|
