最近股市行情很糟，所以很多人的401K都受影响。

401K讲得是长期投资，不用为这短期效应着急。

真要换分配，我和我LG的都是免费，不太清楚是不是有的公司收费。

That's true.  The market behaved a little wild last couple of weeks.  But we should think long-term.  I dont think either Vanguard or Fidelity charge you a fee for allocating your money between funds.  However, if have had a fund less than certain period of time (2 months, for instance) and then you liquidate it, you will have to pay a fee.