| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be very difficult to say | 13 |
|
| 2 | [be] very difficult to say | 13 |
|
| 3 | [is] very difficult to say | 12 |
|
| 4 | 's very difficult to say | 7 |
|
| 5 | is very difficult to say | 5 |
|
