SN4 ""

No	Pattern	Freq
1	it [vb past] when	132
2	it [vb -s] when	111
3	it do when	30
4	it happen when	24
5	it did when	19
6	it [vb infin] when	17
7	it mean when	16
8	it start when	16
9	it happened when	14
10	it have when	13
11	it started when	12
12	it began when	10
13	it had when	10
14	it does when	10
15	it begin when	10
16	it occur when	9
17	it means when	9
18	it came when	9
19	it come when	9
20	it [vb pp] when	8
21	it occurs when	7
22	it appear when	6
23	it hurt when	6
24	it happens when	6
25	it make when	5
26	it seem when	5
27	it [v-ing] when	5
28	it say when	5
29	it depend when	5
30	it feel when	5