SN4 ""

No	Pattern	Freq
1	[noun] it be [adj] for	222
2	[noun sg] it be [adj] for	147
3	[noun] it is [adj] for	143
4	[noun] it was [adj] for	72
5	[noun pl] it be [adj] for	71
6	[noun] it be possible for	35
7	[noun] it be possible for	35
8	[noun] it be necessary for	24
9	[noun] it be necessary for	24
10	[noun] it 's [adj] for	19
11	[noun] it be important for	15
12	[noun] it be impossible for	15
13	[noun] it be important for	15
14	[noun] it be impossible for	15
15	[noun] it be easy for	13
16	[noun prp] it be [adj] for	13
17	[noun] it be [adj -er] for	12
18	[noun] it be usual for	11
19	[noun] it be usual for	11
20	[noun] it be essential for	10
21	[noun] it be essential for	10
22	case it be [adj] for	9
23	time it be [adj] for	9
24	[noun] it be difficult for	9
25	[noun] it be difficult for	9
26	[noun] it be easier for	8
27	[noun] it be good for	7
28	reason it be [adj] for	7
29	way it be [adj] for	7
30	cases it be [adj] for	6