doubtful

adj.难以预测的；难以预料的，未定局的；怀疑的，拿不准的；不明不白

网络解释.可疑的；可疑；怀疑的；可疑可疑的

adj.1.怀疑的释义下的同义词

uncertain questioning incredulous indecisive suspicious wavering distrustful skeptical irresolute unsure disbelieving vacillatin

2.疑虑的释义下的同义词

disputable debatable problematic questionable unbelievable dubious precarious unclear incredible

sure confident certain precise clear evident