SN4 ""

No	Pattern	Freq
1	[adj] [noun] at a [noun sg]	2066
2	[adj] [noun] at a [noun]	2021
3	[adj] [noun sg] at a [noun]	1316
4	[adj] [noun] at a [noun]	1088
5	[adj] [noun] at a time	859
6	[adj] [noun] at a time	859
7	[adj] [noun pl] at a [noun]	772
8	[num] [noun] at a [noun]	740
9	one [noun] at a [noun]	347
10	one [noun] at a [noun]	347
11	[det] [noun] at a [noun]	253
12	[adj] [noun] at an [noun]	147
13	[adj] [noun] at a cost	78
14	[adj] [noun] at a cost	78
15	[adj] [noun] at a [noun prp]	68
16	[num ord] [noun] at a [noun]	60
17	two [noun] at a [noun]	58
18	two [noun] at a [noun]	58
19	[adj] [n mass] at a [noun]	54
20	[adj] day at a [noun]	49
21	few [noun] at a [noun]	48
22	three [noun] at a [noun]	48
23	three [noun] at a [noun]	48
24	few [noun] at a [noun]	48
25	[adj] [noun] at a meeting	48
26	[adj] [noun] at a meeting	48
27	[adj] year at a [noun]	46
28	[adj] week at a [noun]	45
29	[adj] hour at a [noun]	40
30	[adj] step at a [noun]	40