1. must 18.must not
2.can not 19.can
3. can not 20.can not
4.must 21.must
5.can 22.must not
6.can 23.can not
7.can 24.must
8.can 25.must not
9.must 26.can
10.must not 27.can not
11.must not 28.can not
12.can 29.must
13.must 30.must
14.must 31.must not
15.must not
16.must not
17.can