1. understand - understood - understood
2. run - ran - run
3. swim swam swum
4. draw - drew - drawn
5. drink - drank - drunk
6. pay - paid - paid
7. find - found - found
8. choose - chose - chosen
9. buy - bought - bought
10. make - made - made
11. go - went - gone
12. do - did - done
13. get - got - got