Newbee met problems when do some i18n on rails

1. I have download the zh-CN.yml file from
2. I have put this zh-CN.yml in to my locales folder.
3. I have modified the enviorment.rb like follow:
config.i18n.load_path << Dir[File.join(RAILS_ROOT, 'my', 'locales', '*.
config.i18n.default_locale = :'zh-CN'

But, when I restart my server and try to access the rails project via
I've got one message "can't convert Array into String", it comes from
this <%=h distance_of_time_in_words(, item.expiredate, true)
And it seems everything related to data and time got this message.

Any one can help me point out the problem I have?