SN4 ""

No	Pattern	Freq
1	it is [adj] [to-vb] that	1770
2	it is important [to-vb] [that]	482
3	it is [adj] to note [that]	308
4	it is [adj] to say [that]	189
5	it is interesting [to-vb] [that]	183
6	it is [adj] to remember [that]	131
7	it is [adj] to assume [that]	110
8	it is [adj] to believe [that]	108
9	it is easy [to-vb] [that]	102
10	it is reasonable [to-vb] [that]	99
11	it is difficult [to-vb] [that]	97
12	it is fair [to-vb] [that]	88
13	it is hard [to-vb] [that]	77
14	it is possible [to-vb] [that]	73
15	it is [adj] to see [that]	72
16	it is [adj] to ensure [that]	56
17	it is [adj] to realise [that]	52
18	it is [adj] to know [that]	45
19	it is necessary [to-vb] [that]	43
20	it is [adj] to imagine [that]	43
21	it is [adj] to suppose [that]	42
22	it is [adj] to think [that]	40
23	it is true [to-vb] [that]	38
24	it is tempting [to-vb] [that]	33
25	it is sufficient [to-vb] [that]	33
26	it is [adj] to argue [that]	31
27	it is [adj] to recognize [that]	31
28	it is [adj] to stress [that]	30
29	it is [adj] to suggest [that]	29
30	it is safe [to-vb] [that]	27