| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be keep for a long time | 5 |
|
| 2 | be keep [prep] a long time | 5 |
|
| 3 | be keep [prep] a long time | 5 |
|
| 4 | be kept [prep] a long time | 5 |
|
| 5 | be keep for a long time | 5 |
|
