What can be inferred is that tests are inadequate to measure one's language ability.
Explanation:
In "Mother Tongue", Amy Tan discusses the many Englishes she speaks in life, giving special attention to her Chinese mother's broken English. In this excerpt, Tan conveys the idea that school tests are often completely inadequate to measure people's true capacity at something. Tan speaks many Englishes, so to speak. She is capable of understanding her mother's lacking English and to communicate with her in a simpler manner; she is also capable of writing and giving lectures using a perfectly formal English that doesn't sound broken or lacking at all. Still, when she was younger, she performed badly on tests. She was not expected to use her imagination, but to guess what other people wanted her to think. She was never good at it, but that does not mean she is bad at English at all. Her way of viewing the language and how to use it is merely different.
