| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is essential [conj] [adj] | 81 |
|
| 2 | [noun] it is essential [conj] | 39 |
|
| 3 | [noun] is essential [conj] [adj] | 14 |
|
| 4 | [noun] it is [conj] [adj] | 7 |
|
