| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] be [adv] useful for [adj] | 6 |
|
| 2 | [vb mod] be [adv] useful for [adj] | 6 |
|
| 3 | be [adv] useful for [adj] [noun] | 7 |
|
| 4 | be [adv] useful for [adj] [noun pl] | 5 |
|
