No | Pattern | Freq | Relations |
---|---|---|---|
1 | a period of [noun] [art] | 17 | |
2 | a period of [noun] [art] | 17 | |
3 | a period of [noun sg] [art] | 15 | |
4 | a period of [noun] the | 14 | |
5 | a period of [noun] the | 14 | |
6 | a period of time [art] | 8 | |
7 | a period of time [art] | 8 |