How do you define fluency?

A score in a test is a reasonable guide to language ability but it is not the only criteria.

On a resume, having a English-language certificate would be simple to describe language skills; however, it is not always clear what fluency means. The definition of what fluency means can be vague and elusive.

To compare, a native language and a foreign language, the difference is the strength of connections with our emotions and feelings. 

I also think that a language is a part of a country's or an area's culture, but then again it is just a tool to express ourselves. I consider what fluency is that how we fill in the gaps between the languages' property. To follow this concept, I had better to set myself very specific targets to improve my English.