| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | there [verb] been few studies [prep] | 5 |
|
| 2 | there [verb] been few studies of | 5 |
|
| 3 | there [verb] been few studies of | 5 |
|
| 4 | there [verb] been few studies [prep] | 5 |
|
