Are there any other instances or rules for "since" and "for"?
I know that for is used for general periods of time - 2 hours, three days, one month and since is used for a specific time - 1998, January, last week, one month ago.
Thanks so much!
'For' has many other uses as a preposition, without referring to time- it can indicate purpose (I went for a coffee). 'Since' can also be used to mean 'because' (take an umbrella since it's going to rain later)