Choose the prepositions and fill in the suitable blanks.
out, on , back, off, by, for
1. advance = go __
2. continue = go ___
3. pass = go ___
4. reserve = ____
5. fight off = keep ____
6. replace = put ___
7. discourage; postpone = put ___
8. be ready to help = stand ____
9. represent = stand ___
10. extinguish = put ____