| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adj] [is] [adj] [prep] [v-ing] | 136 |
|
| 2 | [adj] [be] useful [prep] [v-ing] | 14 |
|
| 3 | [adj] [is] useful [prep] [verb] | 7 |
|
