1. Assurance
2. Pledge
3. Bond
4. Security
5. Vouch
6. Undertaking
7. Warranty
8. Promise
9. Surety
10. Endorsement
11. Covenant
12. Certify
13. Protection
14. Backing
15. Insure
16. Safeguard
17. Certitude
18. Endorse
19. Safeness
20. Assure
21. Insurement
22. Assent
23. Affirm
24. Certifiable
25. Avouch
26. Suretyship
27. Cert
28. Surety bond
29. Warranty bond
30. Contract

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