To me, one of the most important pieces of imagery, is the Chinese girl that inspires Jing-Mei's mother to make her start piano classes:
I could see why my mother was fascinated by the music. It was being pounded out by a little Chinese girl, about nine years old, with a Peter Pan haircut. The girl had the sauciness of a Shirley Temple. She was proudly modest like a proper Chinese child. And she also did this fancy sweep of a curtsy, so that the fluffy skirt of her white dress cascaded slowly to the floor like the petals of a large carnation.
In any piece of imagery you need to identify how the text engages the fives senses of the reader, and perhaps how other literary techniques are used to do this, such as the simile at the end of this quote comparing the dress to a large carnation.
"Mr. Chong, whom I secretly nicknamed Old Chong, was very strange, always tapping his fingers to the silent music of an invisible orchsta. He looked ancient in my eyes. He had lost most of the h air on the top of his head, and he wore thick glasses and had eyes that alwys looked tired. Vut he must have been younger that I though, since he lived withhis mother and was not yet married. I met Old Lady Chong once, and that was enough. She had a peculiar smell, like a baby that had done something in its pants, and her fingers felt like a dead person's, like an old peach I once found in the back of the refrigerator: its skin just slid off the flesh when I picked it up. "
One I can think of is the image of the mother watching TV and learrning and becomes fixated on the image of the little Chinese girl performing on the Ed Sullivan Show. The narrator describes how her mother 'seemed entranced by the music, a frenzied little piano piece with a mesmerizing quality, which alternated between quick, playful passages and teasing, lilting ones.'