Answer:
1.aboard
2.around
3.under
4.down
5.outside
6.toward
7.During, across
8.under,except
9.beneath
10.before
11.above
12.around,after
13.between
14.among
15.after
16.above,across from
17.in
18.because of,after
19.before,about,from
20.outside,in
