Yes, there's nothing wrong with speaking your native language of course but if you want to be a citizen you should learn English.
True, but America already has a strong workforce. We need people who are going to be beneficial to the country. Immigration used to be harder (in some ways) than it is today, they turned back people at the gate and sent them home.
We really need selective immigration like we used to have, that way immigrants have time to assimilate, that way they can take on the culture, language, etc.