| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be useful for [adj] [noun sg] | 16 |
|
| 2 | be useful [prep] [adj] [noun sg] | 10 |
|
| 3 | are useful [prep] [adj] [noun sg] | 6 |
|
| 4 | is useful [prep] [adj] [noun sg] | 5 |
|
| 5 | be useful in [adj] [noun sg] | 5 |
|
