Speak good english?

After an extensive conservation, I mean conversation with my father of whether it is justifiable to speak proper English in all occasions, I still feel strongly that it is vital to converse in standard English at all times. He has  a strong stand in claiming that as long as the information is carried forward, it is ok to speak in broken English. I, on the other hand think it is ridiculous and outrageous to be unable to  speak your first language well. I mean, if you are fluent in your second language, then, at least thats acceptable. Since you can still fall back on another language. But for a typical Singaporean, to whom I refer to my father, or even my mother, they really arent that well versed in either field. As  such, I heed everyone to take their languages seriously. Dont let your linguistic ability turn out like something above. And please excuse me for the erhem words used above. Its all for fun.