SN4 ""

No	Pattern	Freq
1	that [vb mod] have been [adj]	57
2	that [modal v] have been [adj]	57
3	that [modal v] have been [adj]	57
4	that [modal v] have been [adj]	51
5	that would have been [adj]	36
6	that would have been [adj]	36
7	that [modal v] have been unthinkable	6
8	that should have been [adj]	6
9	that must have been [adj]	6
10	that should have been [adj]	6
11	that might have been [adj]	6
12	that must have been [adj]	6
13	that [modal v] have been unthinkable	6
14	that might have been [adj]	6
15	that [modal v] have been impossible	5
16	that [modal v] have been impossible	5