| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb base] [to-vb] for [adj] hours | 10 |
|
| 2 | [vb base] for about [adj] hours | 7 |
|
| 3 | [vb base] [to-vb] for about [adj] | 7 |
|
| 4 | [to-vb] for about [adj] hours | 6 |
|
