| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be difficult [prep] them [to-vb] | 27 |
|
| 2 | be difficult [prep] them [to-vb] | 27 |
|
| 3 | be difficult for them [to-vb] | 27 |
|
| 4 | be difficult for them [to-vb] | 27 |
|
| 5 | is difficult [prep] them [to-vb] | 12 |
|
| 6 | be difficult [prep] them [to-vb] | 9 |
|
| 7 | was difficult [prep] them [to-vb] | 5 |
|
