| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | more research need to [be] done | 5 |
|
| 2 | more research need to [be] [vb pp] | 5 |
|
| 3 | more research need to [be] do | 5 |
|
| 4 | more research need to [be] [verb] | 5 |
|
