have you heard any of these immigrants saying, "I refuse to learn English." Nobody says that. Why would someone come here and refuse to learn a language that is important to there well being? Not everything is available in spanish, and immigrants know that. Watch any US spanish channel for a few hours some day and count how many commercials have to do with english speaking programs. Programs such as: follow me to america, ingles sin barreras, and many others would not be as big of a seller as they are if immigrants did not want to learn English. You are assumming because it is hard for them to learn English or they just got here that they are refusing when they are not. They struggle to learn the language as would any adult who relocates to another country and tries to learn the language.
We all have a specific set of phonemes that we learned as children, and not all languages share the same phonemes. It is harder for people to learn another language after a certain age, because phonemes are best picked up when you are a young child. Examples: many people who grew up speaking english and try to learn spanish have lots of difficulty rolling their R's, Native Japanese speakers who later learn english will have a lot of trouble differentiating between R's and L's. They would say things like "I Rove to speak EngRish."
