| agree(verb, support, take, acquiesce, verify) |
| assent(verb, support, take, agree, sign) |
| assert(verb, support, state, maintain, back) |
| assume(verb, agree, sign, acknowledge, admit) |
| assure(support, state, maintain, back, confirm) |
| attest to(verb, expression, phrasal verb, support, maintain) |
| autograph(verb, support, take, agree, sign) |
| aver(verb, state, maintain, declare, confirm) |
| avert(verb, support, maintain, back, declare) |
| avouch(verb, state, maintain, declare, confirm) |
| back up(verb, expression, phrasal verb, praise, favor) |
| be responsible for(verb, support, maintain, back, declare) |
| bear(verb, agree, sign, acknowledge, assume) |
| bear testimony(verb, expression, support, maintain, back) |
| boost(verb, support, take, praise, favor) |
| check(prove, verify, substantiate, validate, corroborate) |
| check on(verb, expression, phrasal verb, confirm, story) |
| check up(verb, expression, phrasal verb, confirm, story) |
| cinch(verb, state, maintain, declare, confirm) |
| circumstantiate(verb, support, back, sign, permit) |