| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had be [verb] [prep] | 17603 |
|
| 2 | [verb] be operate [prep] | 66 |
|
| 3 | have be operate [prep] | 63 |
|
| 4 | [vb past] be operate [prep] | 13 |
|
| 5 | had [be] operate [prep] | 13 |
|
