Student or Learner
I know that one of the meanings of "spare" is "refrain from inflicting smth on smn". So can I say, for example, "spare the audience with boring speech"? Is "with" is the right word here, or should it be "from"? Is it a correct sentence in general?
"Spare from" would be proper and in your example it should read, "spare the audience from a boring speech"