SN4 ""

No	Pattern	Freq
31	it be impossible	1565
32	it [be] impossible	1565
33	it [is] impossible	993
34	it is impossible	812
35	it [was/were] impossible	562
36	it was impossible	561
37	it 's impossible	181
38	it [adv] impossible	133
39	it [adv] impossible	132
40	it [verb] impossible	125
41	it [vb past] impossible	77
42	it seem impossible	69
43	it almost impossible	66
44	it almost impossible	66
45	it [vb -s] impossible	45
46	it seemed impossible	42
47	it virtually impossible	32
48	it virtually impossible	32
49	it prove impossible	26
50	it seems impossible	25
51	it become impossible	23
52	it proved impossible	22
53	it becomes impossible	12
54	it became impossible	11
55	it quite impossible	9
56	it quite impossible	9
57	it [be] impossible	6
58	it be impossible	6
59	it impossible [to-vb]	299
60	it impossible [verb]	299