| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficult [to-vb] [art] [adj] [noun] | 353 |
|
| 2 | it [to-vb] [art] [adj] [noun] | 189 |
|
| 3 | it difficult [to-vb] [art] [noun] | 146 |
|
| 4 | it difficult [to-vb] [art] [adj] | 76 |
|
| 5 | it difficult [to-vb] [adj] [noun] | 65 |
|
