| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [art] period of about [adj] | 39 |
|
| 2 | [art] period of about [adj] | 39 |
|
| 3 | a period of about [adj] | 37 |
|
| 4 | a period of about [adj] | 37 |
|
| 5 | [adj] period of about [adj] | 10 |
|
| 6 | [adj] period of about [adj] | 5 |
|
| 7 | period of about [adj] [noun] | 44 |
|
| 8 | period of about [adj] [noun pl] | 43 |
|
| 9 | period of about [adj] years | 15 |
|
| 10 | period of about [adj] year | 15 |
|
| 11 | period of about [adj] month | 11 |
|
| 12 | period of about [adj] months | 11 |
|
| 13 | period of about [adj] weeks | 7 |
|
| 14 | period of about [adj] week | 7 |
|
| 15 | period of about [adj] hour | 6 |
|
| 16 | period of about [adj] hours | 6 |
|
