1. confuse, throw, fox, befuddle, fuddle, bedevil, confound, discombobulate, be
usage: be confusing or perplexing to; cause to be unable to think clearly; "These questions confuse even the experts"; "This question completely threw me"; "This question befuddled even the teacher"
2. confuse, confound, mistake, misidentify
usage: mistake one thing for another; "you are confusing me with the other candidate"; "I mistook her for the secretary"