| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [to-vb] [conj] [art] [noun] | 8284 |
|
| 2 | difficult [to-vb] [art] [noun] | 852 |
|
| 3 | difficult [to-vb] [conj] [art] | 200 |
|
| 4 | difficult [to-vb] [conj] [noun] | 113 |
|
| 5 | difficult [conj] [art] [noun] | 86 |
|
