SN4 ""

No	Pattern	Freq
1	[art] [noun] twenty years	22
2	[art] [noun] twenty years	22
3	[noun] [noun] twenty years	19
4	[adj] [noun] twenty years	17
5	[prep] [noun] twenty years	14
6	[prep] [noun] twenty years	14
7	[noun sg] [noun] twenty years	12
8	the [noun] twenty years	12
9	the [noun] twenty years	12
10	a [noun] twenty years	10
11	a [noun] twenty years	10
12	[pron] [noun] twenty years	9
13	[pos pn] [noun] twenty years	9
14	[adj] [noun] twenty years	8
15	[det] [noun] twenty years	8
16	[noun prp] [noun] twenty years	7
17	[verb] [noun] twenty years	7
18	[noun] [prep] twenty years	157
19	[noun] [prep] twenty years	157
20	[noun] for twenty years	74
21	[noun] for twenty years	74
22	[noun] of twenty years	50
23	[noun] of twenty years	50
24	[noun] [adv] twenty years	28
25	[noun] [adv] twenty years	27
26	[noun] [noun] twenty years	19
27	[noun] in twenty years	16
28	[noun] in twenty years	16
29	[noun] [noun sg] twenty years	13
30	[noun] [adj] twenty years	11