I have tried several times but for some reason my post does not show. Now I'm tired of typing in Chinese.
When trying to improve intonation, I found it is easier for me to stick with the same person for a while. Technically, intonation is different from one person to the other, even for native speakers. Because of that, I normally like to start with somebody who I like his/her voice. I personally think it is easier for a man to emulate a man's voice and women to emulate a woman's voice. I also like to find somebody whose recordings are easy to find along with the transcripts. Keep practicing, someday, you’ll hear the difference.