The so-called memory appearance refers to the image reproduced in the human brain by things that people perceive. The memory content designed in the following activities is not a memory appearance. ['Tom still remembers when she ate Quanjude roast duck in China.', 'Old Li often recalls his hard life in childhood.', 'The beautiful piano sound echoed in her ear.', 'Xiao Hong will already be proficient in reciting multiplication formulas.']