throw (someone) a curve (ball) idiom mainly US and Australian English informal
给（某人）出难题；使（某人）惊讶
to surprise someone with something that is difficult or unpleasant to deal with
Mother Nature threw us a curve ball last winter with record-breaking amounts of snow. 去年冬天的降雪量创下了记录，老天爷真是给我们出了个难题。