| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [conj] it is difficult to know | 17 |
|
| 2 | [noun] it is difficult to know | 8 |
|
| 3 | [coord] it is difficult to know | 7 |
|
| 4 | [subord] it is difficult to know | 6 |
|
| 5 | and it is difficult to know | 5 |
|
| 6 | and it is difficult to know | 5 |
|
| 7 | [noun sg] it is difficult to know | 5 |
|
| 8 | it is [adv] difficult to know | 14 |
|
| 9 | it is [adv] difficult to know | 14 |
|
| 10 | it is difficult to know [adv] | 21 |
|
| 11 | it is difficult to know [Wh adv] | 19 |
|
| 12 | it is difficult to know [pron] | 17 |
|
| 13 | it is difficult to know [Wh det] | 16 |
|
| 14 | it is difficult to know how | 14 |
|
| 15 | it is difficult to know [subord] | 14 |
|
| 16 | it is difficult to know how | 14 |
|
| 17 | it is difficult to know [conj] | 14 |
|
| 18 | it is difficult to know whether | 13 |
|
| 19 | it is difficult to know whether | 13 |
|
| 20 | it is difficult to know what | 11 |
|
| 21 | it is difficult to know what | 11 |
|
| 22 | it is difficult to know which | 5 |
|
| 23 | it is difficult to know where | 5 |
|
| 24 | it is difficult to know where | 5 |
|
| 25 | it is difficult to know which | 5 |
|
