SN4 ""

No	Pattern	Freq
1	it be [verb] and	673
2	it [be] [verb] and	673
3	it [be] [vb pp] and	503
4	it [was/were] [verb] and	338
5	it was [verb] and	329
6	it [is] [verb] and	323
7	it is [verb] and	243
8	it [be] [v-ing] and	131
9	it 's [verb] and	80
10	it [be] [to-vb] and	37
11	it [be] raining and	30
12	it [be] rain and	30
13	it [be] make and	17
14	it [be] do and	14
15	it [be] made and	14
16	it [be] go and	12
17	it [be] call and	11
18	it [be] called and	11
19	it were [verb] and	9
20	it [be] happen and	8
21	it [be] use and	8
22	it [be] used and	8
23	it [be] done and	8
24	it [be] happening and	8
25	it [be] close and	7
26	it [be] closed and	7
27	it [be] write and	7
28	it [be] gone and	7
29	it [be] to try and	7
30	it [be] try and	7