SN4 ""

No	Pattern	Freq
1	at once from	18
2	[prep] once from	18
3	at once from	18
4	[prep] once from	18
5	[verb] once from	5
6	[adv] once from	5
7	once [verb] from	44
8	once [vb pp] from	31
9	once [adv] from	24
10	once [adv] from	24
11	once more from	10
12	once more from	10
13	once [vb past] from	9
14	once [adj] from	8
15	once [adj] from	8
16	once away from	7
17	once away from	7
18	once again from	6
19	once again from	6
20	once from [art]	16
21	once from [art]	16
22	once from the	11
23	once from the	11
24	once from [noun]	10
25	once from a	5