| be suspicious of(verb, doubt, disbelieve) |
| be wary(verb, question) |
| beat(perplex, bewilder, mystify) |
| befog(perplex, bewilder, mystify) |
| befuddle(perplex, bewilder, mystify) |
| bemuse(perplex, bewilder, mystify) |
| bewilder(perplex, mystify) |
| brood(verb, study, perplex, bewilder, mystify) |
| brood over(expression, consider, deliberate) |
| call into question(verb, expression, idiom, oppose, dispute) |
| cast doubt on(expression, idiom, doubt, suspect) |
| cast doubt upon(verb, expression, idiom, phrasal verb, oppose) |
| challenge(verb, oppose, dispute, doubt, suspect) |
| chew over(expression, consider, ponder, reflect) |
| cogitate(consider, ponder, reflect) |
| complicate(perplex, bewilder, mystify) |
| confound(perplex, bewilder, mystify) |
| confuse(perplex, bewilder, mystify) |
| consider(verb, deliberate, ponder, reflect) |
| contemplate(verb, consider, deliberate, ponder, reflect) |