SN4 ""

No	Pattern	Freq
1	at which [noun sg]	363
2	at which [noun pl]	245
3	at which [noun prp]	174
4	at which time	67
5	at which time	66
6	at which [n mass]	27
7	at which point	20
8	at which point	20
9	at which people	16
10	at which people	16
11	at which women	11
12	at which woman	11
13	at which child	10
14	at which children	10
15	at which moment	9
16	at which moment	9
17	at which mr	8
18	at which mr	8
19	at which [letter]	7
20	at which price	7
21	at which stage	6
22	at which accounts	6
23	at which account	6
24	at which stage	6
25	at which price	6
26	at which material	6
27	at which words	5
28	at which word	5