| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] [prep] a period of [noun] | 68 |
|
| 2 | [adv] [prep] a period of [noun sg] | 51 |
|
| 3 | [adv] [prep] a [noun] of time | 36 |
|
| 4 | [adv] [prep] a [noun sg] of time | 35 |
|
| 5 | [adv] [prep] [art] period of time | 32 |
|
| 6 | [adv] [prep] [art] period of time | 32 |
|
| 7 | [adv] [prep] a period [prep] time | 31 |
|
| 8 | [adv] [prep] a period of time | 31 |
|
| 9 | [adv] [prep] a period [prep] time | 31 |
|
| 10 | [adv] [prep] a period of time | 31 |
|
| 11 | [adv] [prep] a period of time | 31 |
|
| 12 | [adv] [prep] a period of time | 31 |
|
| 13 | [adv] [prep] a period of time | 31 |
|
