| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | is useful for [verb] | 39 |
|
| 2 | useful for [verb] [adj] | 38 |
|
| 3 | is useful [verb] [adj] | 33 |
|
| 4 | is useful for [adj] | 26 |
|
| 5 | is for [verb] [adj] | 6 |
|
