SN4 ""

No	Pattern	Freq
1	have [been] [vb pp] for years [prep]	9
2	have [been] [vb pp] for years [prep]	9
3	[noun] have [been] [vb pp] for years	16
4	[noun sg] have [been] [vb pp] for years	9
5	[noun pl] have [been] [vb pp] for years	5
6	have [adv] [been] [vb pp] for years	10
7	have [not/n't] [been] [vb pp] for years	9
8	have not [been] [vb pp] for years	9
9	have not [been] [vb pp] for years	5
10	have [been] [vb pp] for [adj] years	162
11	have [been] [vb pp] for [num] years	92
12	have [been] [vb pp] for [det] years	70
13	have [been] [vb pp] for many years	50
14	have [been] [vb pp] for many years	50
15	have [been] [vb pp] for two years	15
16	have [been] [vb pp] for two years	15
17	have [been] [vb pp] for some years	15
18	have [been] [vb pp] for some years	15
19	have [been] [vb pp] for three years	14
20	have [been] [vb pp] for three years	14
21	have [been] [vb pp] for seven years	8
22	have [been] [vb pp] for seven years	8
23	have [been] [vb pp] for five years	7
24	have [been] [vb pp] for five years	7
25	have [been] [vb pp] for 12 years	5
26	have [been] [vb pp] for several years	5
27	have [been] [vb pp] for several years	5
28	have [been] [vb pp] for 12 years	5