| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] [prep] a period of [noun] | 68 |
|
| 2 | [adv] [prep] a [noun] of weeks | 49 |
|
| 3 | [adv] [prep] a period of [noun pl] | 17 |
|
| 4 | [adv] [prep] a period of weeks | 5 |
|
| 5 | [adv] [prep] [art] period of weeks | 5 |
|
| 6 | [adv] [prep] a period [prep] weeks | 5 |
|
| 7 | [adv] [prep] [art] period of weeks | 5 |
|
| 8 | [adv] [prep] a period of weeks | 5 |
|
| 9 | [adv] [prep] a period of week | 5 |
|
