Translation:My daughter is 17 years old.
I am American and I know what you mean. It does get easier to distinguish characters and the tones of characters with time and consistent practice. Plus, I use Google Translate to get a "second opinion" of how a Chinese sentence sounds like. And I use the Google Translate's microphone feature to pronounce it/speak it myself. I repeat saying the Chinese sentences over and over again until I get the correct translation appearing on Google Translate, and then I know i am pronouncing it correctly myself. So, for repeated "hearing a Chinese sentence" and "saying a Chinese sentence" (and for getting the pinyin of a Chinese sentence)- Google Chinese to English Translation is my Duolingo companion tool!