Here are some examples of sentences using the word: surely. Surely, you can make an exception for me. Will you wait for me? Surely! Surely, you remember. Surely means yes or it can be used to emphasize the speaker's firm belief that what they are saying is true and often their surprise that there is any doubt of this. You can see this in each example. Surely and really do not mean the same thing. To me, using surely here doesn't sound like good grammar. Really means very, or emphasizes the significance of whatever it is put in front of. Certainly and surely are synonyms. Synonyms are words that mean the same thing so you can exchange them. Certainly, you can make an exception for me. Will you wait for me? Certainly! Certainly you remember. Using the word really in place of certainly/surely: Really, you can make an exception for me. Will you wait for me? Really! Really, you remember. As you can see the meaning of the sentences have now changed dramatically or in some cases do not make sense. This is the case in the sentence that was corrected for you. I would still correct the sentence like this: I really hope nothing else with break now since it really is an old bicycle. Hope that helps

I’d definitely agree that ‘really’ works best in your setence. The three words are similar, but are used in slightly different ways to change the tone or sense of a statement. You can say ‘really’ to emphasise any statement. So in your example, it gives the idea that because your bicycle has broken a lot before and it’s likely to break again, you are hoping very much that it doesn’t break again. This is really (!) common and you’ll hear people use it all the time in all sorts of contexts. ‘Certainly’ might be used if you’re reaffirming or emphatically contradicting a statement someone else has just made. Eg. “Do you think your bicycle is going to break again?” “Well I certainly hope it doesn’t!” I wouldn’t use 'surely' in your example sentence. It just doesn’t sound natural. You do hear it used when someone is questioning something that they think is true but unlikely. Eg “Surely your bicycle hasn’t broken again? That’s the third time this month!” This is really the only situation in which I'd use the word 'surely'.