很接近‘到目前爲止’的意思。 e.g.到目前爲止，他的表現還不錯。> So far, his performance has been good.

The phrase "So far" describes the present state of something. Example: "So far her grades have been good, but because she is lazy, they may drop" In this example, "so far" is used to describe that up until the current time, the girls grades were good. So basically, so far is used to describe whatever situation "up until the current time". Example 2: "So far" used in conversation: Girl 1: "Tom is a very sad man" Girl 2: "Really? I'm surprised to hear that. Tom has always been a happy man, SO FAR as I know..." Up until that current time, Girl 2 had always thought Tom was a happy man. I hope you understand now! :)

Form of insofar Main Entry: insofar as Function: conjunction Date: 15th century : to the extent or degree that <we agree only insofar as the budget is concerned> so far 1 : to a certain extent, degree, or distance <when the water rose so far, the villagers sought higher ground> 2 : up to the present <has written just one novel so far> — thus far : so far <thus far our findings have been negative> http://www.merriam-webster.com/dictionary/so%20far

when its SO far xD