SN4 ""

No	Pattern	Freq
1	who had [adv] been [vb pp]	196
2	who had [adv] been [verb]	178
3	who had [not/n't] been [verb]	61
4	who had not been [verb]	61
5	who had not been [verb]	56
6	who had [adv] been [v-ing]	42
7	who had already been [verb]	25
8	who had already been [verb]	25
9	who had also been [verb]	24
10	who had also been [verb]	24
11	who had just been [verb]	16
12	who had previously been [verb]	16
13	who had just been [verb]	16
14	who had previously been [verb]	16
15	who had never been [verb]	13
16	who had never been [verb]	13
17	who had [adv] been treat	12
18	who had recently been [verb]	11
19	who had recently been [verb]	11
20	who had [adv] been treated	11
21	who had earlier been [verb]	7
22	who had [adv] been see	7
23	who had early been [verb]	7
24	who had hitherto been [verb]	6
25	who had [adv] been seen	6
26	who had hitherto been [verb]	6
27	who had n't been [verb]	5
28	who had [adv] been admitted	5
29	who had [adv] been admit	5
30	who had originally been [verb]	5