| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a period [prep] [noun] | 608 |
|
| 2 | [prep] a period [prep] [noun sg] | 477 |
|
| 3 | [prep] a [noun] [prep] time | 410 |
|
| 4 | [prep] a [noun sg] [prep] time | 408 |
|
| 5 | [prep] [art] period [prep] time | 256 |
|
| 6 | [prep] a period [prep] time | 240 |
|
| 7 | [prep] a period [prep] time | 240 |
|
| 8 | [prep] a period [prep] time | 240 |
|
