adv. 無疑;當然;確定;肯定;
?? certain確實的+ly副詞后綴,…地 → 確實地,一定地,當然地
"I shall certainly keep a beady eye on his behaviour."
我一定會時刻睜大眼睛提防他的行為。
近義:indeed, indubitably, inevitably, infallibly, assuredly, absolutely
反義:hesitatingly, hesitatively, indecisively, arguably, tentatively, wonderingly