doubt

have (your) doubts  

have no doubts at all  

raise doubts =make people have doubt 

express/voice doubts =say that you have doubts  

nagging/lingering doubt =a doubt that does not go away  

serious/grave doubts  

an element of doubt =a  slight doubt  

there is little/some/no doubt (that) =used to talk about how certain you are about something 

not the slightest doubt =no doubt at all  

without a shadow of a doubt =with no doubt at all  

cast/throw doubt on something =make someone feel  

uncertain about something