| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [adv] difficult to determine | 15 |
|
| 2 | it is [adv] difficult to determine | 15 |
|
| 3 | it is often difficult to determine | 5 |
|
| 4 | it is often difficult to determine | 5 |
|
| 5 | it is difficult to determine [art] | 9 |
|
| 6 | it is difficult to determine [art] | 9 |
|
| 7 | it is difficult to determine the | 7 |
|
| 8 | it is difficult to determine the | 7 |
|
| 9 | it is difficult to determine [pron] | 5 |
|
