| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | shown to be [adj] [prep] | 114 |
|
| 2 | shown to be [adj] [prep] | 113 |
|
| 3 | [verb] to be essential [prep] | 15 |
|
| 4 | [vb pp] to be essential [prep] | 9 |
|
| 5 | shown to be essential [prep] | 5 |
|
| 6 | shown to [be] essential [prep] | 5 |
|
| 7 | show to be essential [prep] | 5 |
|
| 8 | shown [prep] be essential [prep] | 5 |
|
| 9 | shown to be essential [prep] | 5 |
|
| 10 | shown [prep] be essential [prep] | 5 |
|
