SN4 ""

No	Pattern	Freq
1	[be] a major problem	78
2	be a major problem	78
3	[verb] a major problem	59
4	[is] a major problem	37
5	is a major problem	32
6	[adv] a major problem	30
7	[adv] a major problem	18
8	become a major problem	15
9	[be] a major problem	15
10	[prep] a major problem	15
11	[was/were] a major problem	15
12	be a major problem	15
13	[prep] a major problem	15
14	[vb -s] a major problem	13
15	was a major problem	12
16	[not/n't] a major problem	12
17	[vb infin] a major problem	12
18	not a major problem	12
19	have a major problem	11
20	[vb pp] a major problem	11
21	[vb past] a major problem	10
22	not a major problem	10
23	as a major problem	8
24	as a major problem	8
25	still a major problem	7
26	still a major problem	7
27	[vb base] a major problem	7
28	[been] a major problem	6
29	[conj] a major problem	6
30	been a major problem	6