| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [adj] for | 2028 |
|
| 2 | it is essential [prep] | 101 |
|
| 3 | [pron] is essential for | 92 |
|
| 4 | it be essential for | 90 |
|
| 5 | it [be] essential for | 90 |
|
| 6 | it [is] essential for | 74 |
|
