| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [prep] [adv] a month | 30 |
|
| 2 | [prep] [prep] [adv] a month | 30 |
|
| 3 | [prep] [prep] [adv] a month | 30 |
|
| 4 | [prep] [prep] [adv] a month | 30 |
|
| 5 | [prep] at [adv] a month | 29 |
|
| 6 | [prep] at [adv] a month | 29 |
|
| 7 | [prep] [prep] least a month | 29 |
|
| 8 | [prep] [prep] least a month | 29 |
|
| 9 | for [prep] [adv] a month | 24 |
|
