| sponsor(verb, give) |
| undertake(verb, catch, declare, engage, contract) |
| validate(verb, support, state, maintain, back) |
| vouch for(verb, expression, phrasal verb, support, guarantee) |
| affirmation |
| allege(verb, state, maintain, agree, allow) |
| assent(noun, verb, declare, commit, undertake) |
| countersign(verb, guarantee) |
| engage(verb, pass, declare, contract, commit) |
| give evidence(verb, expression, idiom, state, maintain) |
| okay(verb, support, state, give, maintain) |
| swear to(verb, expression, support, give, back) |
| adduce(verb, state, maintain, declare, cite) |
| agree(verb, pass, allow, catch, admit) |
| announce(verb, state, maintain, agree, allow) |
| assert under oath(expression, idiom, support, guarantee) |
| assertion |
| avowal |
| back up(expression, support, verify, guarantee, substantiate) |
| bear out(verb, expression, phrasal verb, support, back) |