You use surely for emphasis when you are objecting to something that has been said or done.
Don't use 'surely' simply to give strong emphasis to a statement. Use definitely.
In British English, you don't use 'surely' when you are agreeing with something that has been said, or confirming that something is true. Use certainly.
American speakers use both surely and certainly to agree with requests and statements.
Don't use 'surely' to say emphatically that something will happen in the future. Use definitely or certainly.
Don't use 'surely' to emphasize that something is what you would expect in particular circumstances. Use naturally.
| Adv. | 1. | naturally - as might be expected; "naturally, the lawyer sent us a huge bill" unnaturally - in a manner at variance with what is natural or normal; "The early Church not unnaturally adopted the position that failure to see the messianic character of his work was really caused by the people's own blindness" |
| 2. | naturally - according to nature; by natural means; without artificial help; "naturally grown flowers" artificially, by artificial means, unnaturally - not according to nature; not by natural means; "artificially induced conditions" | |
| 3. | naturally - through inherent nature; "he was naturally lazy" | |
| 4. | naturally - in a natural or normal manner; "speak naturally and easily" unnaturally - in an unnatural way; "his other arm lay across his chest, unnaturally, as if placed there deliberately, for a purpose" |