SN4 ""

No	Pattern	Freq
1	an [noun sg] [verb] the [noun]	1701
2	an [noun sg] [verb] the [noun sg]	1342
3	an [noun sg] [to-vb] the [noun]	1287
4	an attempt [verb] the [noun]	504
5	an [noun sg] [verb] the [noun pl]	282
6	an [noun sg] [v-ing] the [noun]	209
7	an effort [verb] the [noun]	176
8	an opportunity [verb] the [noun]	113
9	an [noun sg] [vb -s] the [noun]	101
10	an [noun sg] [verb] the [noun prp]	63
11	an [noun sg] [vb past] the [noun]	56
12	an order [verb] the [noun]	40
13	an injunction [verb] the [noun]	38
14	an obligation [verb] the [noun]	32
15	an hour [verb] the [noun]	32
16	an [noun sg] reduce the [noun]	31
17	an agreement [verb] the [noun]	31
18	an [noun sg] to reduce the [noun]	31
19	an [noun sg] [vb base] the [noun]	28
20	an invitation [verb] the [noun]	28
21	an [noun sg] improve the [noun]	23
22	an [noun sg] to improve the [noun]	23
23	an [noun sg] involve the [noun]	22
24	an [noun sg] [verb] the problem	21
25	an [noun sg] have the [noun]	20
26	an [noun sg] [vb pp] the [noun]	19
27	an offer [verb] the [noun]	19
28	an [noun sg] increase the [noun]	19
29	an [noun sg] prevent the [noun]	18
30	an incentive [verb] the [noun]	18