SN4 ""

No	Pattern	Freq
1	it [adj] [to-vb] the [adj] [noun]	131
2	it [adj] [to-vb] the [adj] [noun]	120
3	it [adj] [to-vb] the [adj] [noun]	115
4	it [adj] [to-vb] the [adj] [noun sg]	88
5	it [adj] [to-vb] the [adj] [noun pl]	41
6	it difficult [to-vb] the [adj] [noun]	35
7	it difficult [to-vb] the [adj] [noun]	35
8	it possible [to-vb] the [adj] [noun]	20
9	it possible [to-vb] the [adj] [noun]	20
10	it easy [to-vb] the [adj] [noun]	18
11	it [adj -er] [to-vb] the [adj] [noun]	16
12	it hard [to-vb] the [adj] [noun]	12
13	it easier [to-vb] the [adj] [noun]	12
14	it hard [to-vb] the [adj] [noun]	11
15	it impossible [to-vb] the [adj] [noun]	8
16	it impossible [to-vb] the [adj] [noun]	8
17	it necessary [to-vb] the [adj] [noun]	7
18	it necessary [to-vb] the [adj] [noun]	7
19	it [adj] [to-vb] the national [noun]	6
20	it [adj] [to-vb] the national [noun]	6
21	it [adj] [to-vb] the [num] [noun]	6
22	it easy [to-vb] the [adj] [noun]	6
23	it [adj] [to-vb] the necessary [noun]	5
24	it [adj] [to-vb] the right [noun]	5
25	it [adj] [to-vb] the right [noun]	5
26	it [adj] to maintain the [adj] [noun]	5
27	it [adj] [to-vb] the necessary [noun]	5