| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [is] [v-ing] to be difficult for | 5 |
|
| 2 | [be] [v-ing] to be difficult for | 5 |
|
| 3 | be [v-ing] to be difficult for | 5 |
|
| 4 | 's [v-ing] to be difficult for | 5 |
|
| 5 | [v-ing] to be [adv] difficult for | 6 |
|
| 6 | [v-ing] to be [adv] difficult for | 6 |
|
| 7 | [v-ing] to be very difficult for | 5 |
|
| 8 | [v-ing] to be very difficult for | 5 |
|
