SN4 ""

No	Pattern	Freq
1	[noun] is [to-vb] [adv]	1167
2	[noun sg] is [to-vb] [adv]	992
3	[pron] is [to-vb] [adv]	182
4	[verb] is [to-vb] [adv]	150
5	[pers pn] is [to-vb] [adv]	135
6	[adj] is [to-vb] [adv]	117
7	it is [to-vb] [adv]	105
8	it is [to-vb] [adv]	105
9	do is [to-vb] [adv]	99
10	[to-vb] is [to-vb] [adv]	88
11	[noun pl] is [to-vb] [adv]	85
12	[noun prp] is [to-vb] [adv]	81
13	[det] is [to-vb] [adv]	75
14	to do is [to-vb] [adv]	72
15	aim is [to-vb] [adv]	69
16	aim is [to-vb] [adv]	67
17	[adv] is [to-vb] [adv]	64
18	[adv] is [to-vb] [adv]	56
19	this is [to-vb] [adv]	35
20	this is [to-vb] [adv]	35
21	that is [to-vb] [adv]	31
22	that is [to-vb] [adv]	31
23	problem is [to-vb] [adv]	28
24	problem is [to-vb] [adv]	27
25	project is [to-vb] [adv]	24
26	[adj] is [to-vb] [adv]	23
27	[Wh det] is [to-vb] [adv]	22
28	[vb infin] is [to-vb] [adv]	22
29	which is [to-vb] [adv]	21
30	idea is [to-vb] [adv]	21