I was writing the phrase "I will keep you apprised of the situation" in an email the other day when I was forced to check whether it is "apprised" or "appraised". It is the former of course.
"To apprise someone" is to inform him/her of something.
"To appraise someone" is assess his/her value.
Very, very different.
To remember the difference, it is useful to remember that we can get an item of jewellery "appraised".