SN4 ""

No	Pattern	Freq
1	it be sometimes [adj] [verb]	127
2	it [be] sometimes [adj] [to-vb]	126
3	it [be] sometimes [adj] [verb]	114
4	it [is] sometimes [adj] [verb]	113
5	it is sometimes [adj] [verb]	100
6	it [be] sometimes difficult [verb]	30
7	it [be] sometimes difficult [verb]	30
8	it [be] sometimes possible [verb]	22
9	it [be] sometimes possible [verb]	22
10	it [be] sometimes hard [verb]	15
11	it [be] sometimes hard [verb]	15
12	it [be] sometimes useful [verb]	15
13	it [be] sometimes useful [verb]	15
14	it was sometimes [adj] [verb]	14
15	it [was/were] sometimes [adj] [verb]	14
16	it 's sometimes [adj] [verb]	13
17	it [be] sometimes necessary [verb]	10
18	it [be] sometimes necessary [verb]	10
19	it [be] sometimes [adj -er] [verb]	10
20	it [be] sometimes easy [verb]	7
21	it [be] sometimes good [verb]	6
22	it [be] sometimes easier [verb]	5
23	it [be] sometimes [adj] use	5