SN4 ""

No	Pattern	Freq
1	[noun pl] at a [noun sg]	1601
2	[noun pl] at a [noun]	1583
3	[noun pl] at a time	500
4	[noun pl] at a time	500
5	[noun pl] at an [noun]	131
6	[noun pl] at a [noun prp]	90
7	[noun pl] at a cost	76
8	[noun pl] at a cost	76
9	hours at a [noun]	59
10	[noun pl] at a meeting	50
11	[noun pl] at a meeting	50
12	weeks at a [noun]	46
13	days at a [noun]	45
14	[noun pl] at a rate	44
15	[noun pl] at a rate	44
16	months at a [noun]	41
17	years at a [noun]	36
18	[noun pl] at a price	31
19	[noun pl] at a price	31
20	minutes at a [noun]	29
21	shares at a [noun]	26
22	[noun pl] at a glance	21
23	[noun pl] at a glance	21
24	[noun pl] at a average	21
25	[noun pl] at a average	21
26	[noun pl] at a level	19
27	[noun pl] at a level	19
28	[noun pl] at a distance	19
29	[noun pl] at a distance	19
30	[noun pl] at a conference	18