| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] [verb] [prep] a time | 21 |
|
| 2 | [verb] [prep] a considerable time | 17 |
|
| 3 | [modal v] [verb] [prep] a considerable | 17 |
|
| 4 | [modal v] [verb] a considerable time | 8 |
|
