How does tan build a central idea of her story in the excerpt? tan gives an example of a test question to support the idea that more efforts must be made in the home to expose children to standard english. Tan relates a story about taking an achievement test to support the idea that english curricula must be structured more like math curricula. Tan discusses achievement tests to support the idea that language cannot be separated from the personal meanings and experiences attached to it. Tan describes her experience with achievement tests to support the idea that published authors are most qualified to write test questions for students.