SN4 ""

No	Pattern	Freq
1	[adv] known how	68
2	[verb] known how	44
3	have known how	44
4	[not/n't] known how	41
5	not known how	41
6	not known how	36
7	[adv] known how	27
8	[vb past] known how	21
9	[vb infin] known how	21
10	have known how	20
11	had known how	14
12	yet known how	10
13	yet known how	10
14	'd known how	7
15	always known how	6
16	always known how	6
17	[pron] known how	5
18	[pers pn] known how	5
19	n't known how	5
20	known [prep] how	16
21	known [prep] how	16
22	known [adv] how	15
23	known [adv] how	15
24	known about how	13
25	known about how	13
26	known exactly how	10
27	known exactly how	10
28	known how [adj]	41
29	known how [verb]	34
30	known how [to-vb]	34