No | Pattern | Freq | Relations |
---|---|---|---|
1 | [noun] over a prolonged period | 12 | |
2 | [noun sg] over a prolonged period | 6 | |
3 | over a prolonged period [prep] | 9 | |
4 | over a prolonged period [prep] | 9 | |
5 | over a prolonged period of | 8 | |
6 | over a prolonged period of | 8 |