Hi Alc
alc24“1She sure knows how to sell herself/surely knows how to sell...”
I think there would usually be a difference in meaning in those two sentences.
- She sure knows how to sell herself.
The word sure is used to make an emphatic statement of an obvious fact -- the speaker thinks she is extremely adept at selling herself, and believes this will be equally obvious to other people. Using the word sure in this sentence suggests that she knows much more than just the basics of selling herself. This use of sure would generally be considered fairly informal, but it is an extremely common way to use sure.
- She surely knows how to sell...
This may sometimes be used with a meaning similar to what I mentioned above, however I'd say it would be a fairly uncommon way to use surely (at least in the US). Instead, using surely in that sentence suggests a situation in which the speaker is reacting to someone else's apparent doubt that she knows how to sell at all. In this case, the speaker would not be stating that she is extremely good at selling, but rather that it must be true that she knows generally how to sell and that it does not seem possible that she doesn't know at least the basics of selling.
alc24 “2 She knows to do that./She knows not to act like that.”
- She knows to do that. = She knows that she should do or needs to do that.
- She knows not to act like that. = She knows that she should not act like that.