SN4 ""

No	Pattern	Freq
1	[noun] at a time [Wh adv]	427
2	[noun sg] at a time [Wh adv]	266
3	[verb] at a time [Wh adv]	227
4	[noun pl] at a time [Wh adv]	112
5	[adj] at a time [Wh adv]	92
6	[vb pp] at a time [Wh adv]	87
7	[adv] at a time [Wh adv]	74
8	come at a time [Wh adv]	68
9	[adj] at a time [Wh adv]	55
10	[adv] at a time [Wh adv]	52
11	[vb past] at a time [Wh adv]	49
12	[conj] at a time [Wh adv]	46
13	[vb -s] at a time [Wh adv]	41
14	[noun prp] at a time [Wh adv]	40
15	comes at a time [Wh adv]	33
16	[coord] at a time [Wh adv]	32
17	be at a time [Wh adv]	26
18	[be] at a time [Wh adv]	26
19	[v-ing] at a time [Wh adv]	25
20	came at a time [Wh adv]	24
21	and at a time [Wh adv]	24
22	and at a time [Wh adv]	24
23	[det] at a time [Wh adv]	20
24	[adv prt] at a time [Wh adv]	20
25	was at a time [Wh adv]	19
26	[was/were] at a time [Wh adv]	19
27	this at a time [Wh adv]	18
28	this at a time [Wh adv]	18
29	[pron] at a time [Wh adv]	17
30	[pers pn] at a time [Wh adv]	16