long-term capital loss

On the 1099-B from the broker the sale will be listed ... bought $5000 - sold $4335 = loss $665 period ... it is just that simple.  What happened to the value while you owned it is immaterial.  

And you should have been reporting any dividends each year.  If the dividends were reinvested and bought more shares be sure to add all the purchases to the cost.  A reinvested dividend is really 2 transactions.  A Dividend and then a Buy.  So you might even have a bigger loss.  

But that's not how it appears in the 1099-B form. It shows the gross proceeds of over 4,000 and total gain becomes over 3,000. I cannot understand it! 

I would contact the broker if you believe their form is incorrect.  

It doesn't show your Cost for the shares?  The cost basis on the 1099B may be wrong.    Did you sell ALL the shares in the account and fund?   Did you just buy 1 fund?  

there seems to be three kinds funds under this mutual fund account I opened. so, there are three gross proceeds, cost basis etc listed in the 1099B form. However, one of them (the largest sum) shows nothing in the "cost or other basis" box and said its basis is not reported to IRS.  

I did sell all the shares. 

I phoned them to sell and basically closed the account. You think I should contact them to find out?

Thanks! 

OK ... Look  at the 1099-B carefully ... seems like there are long term covered, short term covered and undetermined sales all of which comprise the total sale ... if you are not understanding how this is reported then talk to the broker to get educated.