| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a period [prep] | 1754 |
|
| 2 | a period [prep] [noun sg] | 814 |
|
| 3 | [prep] a [prep] [noun sg] | 61 |
|
| 4 | [prep] a period [noun sg] | 20 |
|
| 5 | [prep] period [prep] [noun sg] | 13 |
|
