SN4 ""

No	Pattern	Freq
1	[verb] in recent years	418
2	[vb pp] [prep] recent years	342
3	have [prep] recent years	46
4	[vb -s] [prep] recent years	27
5	[v-ing] [prep] recent years	27
6	has [prep] recent years	22
7	increase [prep] recent years	20
8	decline [prep] recent years	20
9	increased [prep] recent years	17
10	declined [prep] recent years	16
11	develop [prep] recent years	15
12	developed [prep] recent years	15
13	[vb base] [prep] recent years	15
14	made [prep] recent years	13
15	make [prep] recent years	13
16	[vb past] [prep] recent years	12
17	[verb] over recent years	12
18	have [prep] recent years	12
19	change [prep] recent years	11
20	[to-vb] [prep] recent years	11
21	changed [prep] recent years	11
22	occurred [prep] recent years	9
23	occur [prep] recent years	9
24	had [prep] recent years	8
25	improve [prep] recent years	8
26	publish [prep] recent years	8
27	improved [prep] recent years	7
28	use [prep] recent years	7
29	expand [prep] recent years	7
30	used [prep] recent years	7