| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | how difficult it is [verb] | 44 |
|
| 2 | how difficult it is [to-vb] | 39 |
|
| 3 | how difficult it is to get | 10 |
|
| 4 | how difficult it is get | 10 |
|
| 5 | how difficult it is [v-ing] | 5 |
|
