[match:group] M1: "(2 + x)" M2: "(3)" [fail:group] F1: "22" F2: "y" [match:factor] M1: "-2" M2: "+22" M3: "-2.71828" M4: "-x" M5: "(2 + x)" M6: "-(a * b)" [fail:factor] F1: "x4" F2: "- 2" [match:term] M1: "2 * 4" M2: "3x" M3: "5 / 2" M4*: "5 / 2x" M5: "5 / -2x" M6: "-3*2y" M7: "4x" M8: "-2x" M9: "20 / 2 * 2" M10: "20 / (2 * 2)" [fail:term] F1: "2 + 4" F2: "4 - 5" [match:expression] M1: "3 + x" M2: "-5 - -4x" M3: "(a + b)(a - b)" M4: "a - 5 + b" M5: "-5 - +4x" M6: "5 - 4 + 3" M7: "5 - (4 + 3)" [fail:expression] F1: "-5 - - 4x"