SN4 ""

No	Pattern	Freq
31	it is difficult tell	17
32	it is difficult to tell	17
33	it is difficult to identify	16
34	it is difficult to decide	16
35	it is difficult identify	16
36	it is difficult decide	16
37	it is difficult predict	14
38	it is difficult to predict	14
39	it is difficult to accept	13
40	it is difficult accept	13
41	it is difficult envisage	13
42	it is difficult to envisage	13
43	it is difficult to explain	13
44	it is difficult argue	13
45	it is difficult explain	13
46	it is difficult to argue	13
47	it is difficult define	12
48	it is difficult to separate	12
49	it is difficult to establish	12
50	it is difficult separate	12
51	it is difficult compare	12
52	it is difficult to compare	12
53	it is difficult to define	12
54	it is difficult establish	12
55	it is difficult judge	11
56	it is difficult to obtain	11
57	it is difficult give	11
58	it is difficult put	11
59	it is difficult to put	11
60	it is difficult to judge	11