| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be difficult to think [prep] [adj] | 7 |
|
| 2 | [be] difficult to think [prep] [adj] | 7 |
|
| 3 | [is] difficult to think [prep] [adj] | 5 |
|
| 4 | is difficult to think [prep] [adj] | 5 |
|
| 5 | difficult to think [prep] [art] [adj] | 7 |
|
| 6 | difficult to think [prep] [art] [adj] | 7 |
|
| 7 | difficult to think [prep] a [adj] | 6 |
|
| 8 | difficult to think [prep] a [adj] | 6 |
|
| 9 | difficult to think [prep] [adj] [noun] | 8 |
|
| 10 | difficult to think [prep] [adj] [noun pl] | 5 |
|
