SN4 ""

No	Pattern	Freq
1	must be [adv] [adj]	713
2	must be [adv] [adj]	711
3	must be [art] [adj]	662
4	must be [art] [adj]	662
5	must be a [adj]	502
6	must be a [adj]	406
7	must be [verb] [adj]	284
8	must be [vb pp] [adj]	218
9	must be very [adj]	162
10	must be very [adj]	162
11	must be the [adj]	150
12	must be the [adj]	150
13	must be an [adj]	96
14	must be [prep] [adj]	89
15	must be [prep] [adj]	89
16	must be make [adj]	79
17	must be made [adj]	78
18	must be [adj] [adj]	77
19	must be [v-ing] [adj]	55
20	must be [pron] [adj]	53
21	must be more [adj]	46
22	must be more [adj]	46
23	must be [det] [adj]	46
24	must be keep [adj]	45
25	must be kept [adj]	45
26	must be some [adj]	37
27	must be quite [adj]	37
28	must be some [adj]	37
29	must be quite [adj]	37
30	must be [indef pn] [adj]	36