| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | for [prep] [adv] a | 179 |
|
| 2 | for [prep] a century | 66 |
|
| 3 | [prep] [adv] a century | 48 |
|
| 4 | for [adv] a century | 29 |
|
