Student or Learner
Would you be kind enough to tell me whether “certainly” and “surely” are perfectly interchangeable?
I know the following three definitions of the adjective “certainly”:
- Undoubtedly; definitely: This is certainly not my writing.
- By all means; of course: You may certainly join us.
- Surely: They certainly are hard workers.
As a matter of fact I know likewise that:
Statements using “certainly” show the speaker has no doubt that he is right. The word usually follows an auxiliary, precedes a main verb.
She certainly dyes her hair. (I am quite sure this is true.)
Our car can certainly go as fast as theirs. ( I am certain of this.)
Statements with “surely” require confirmation of what is probably true by a second speaker. The word is usually first or last in the sentence.
Surely you noticed that the new people have arrived.
You noticed that the new people have arrived, surely. (You did, didn’t you?)
Thank you for your efforts.