check up on

confirm determine divine double-check find out verify

check dig discover establish eye eyeball fix identify learn peg read see settle size tell

catch on check out get down cold get down pat get hold of get it down get the hang of learn the ropes make certain make sure pick up pick up on size up

disprove invalidate

aid assist confuse destroy help ignore look away miss misunderstand neglect overlook unsettle

authenticate certify check corroborate demonstrate double-check establish find out justify prove substantiate

attest debunk document eye eyeball peg settle size support test try

add up bear out check out check up hold up make certain make sure pan out size up stand up

conceal confuse contradict deny discredit disprove hide invalidate reject