副词形式是certainly，例如：
1、I can certainly feel the effects of too many late nights.我当然能感受到熬夜太多产生的影响。
2、Beating the world champions is certainly a big ask for the team.这个队要打败世界冠军当然难度很大。
3、Certainly， the early years are crucial to a child's development.毫无疑问，幼年对儿童的成长至关重要。
副词: certainly
adv. 当然行（用于回答）必定She certainly knows what's what.
她当然知道轻重缓急。
I'm certainly not scared of him.
我当然不怕他。
The story is almost certainly false.
这个故事几乎肯定是虚构的。
I'm certainly never going there again.
我肯定不会再去那里了。
