This is a slippery question, but here’s someone with 28 years of experience and research data to answer the question: How Long Does it Take to Learn Chinese?
For more about what’s reasonable to expect re: Chinese language acquisition, see:
- Learning Mandarin: Realistic Expectations
- How long does it take to get fluent in Chinese? (from Sinosplice – quoting none other than Da Shan himself)
Thanks for the link! In a nutshell, the learning never ends.