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Filed Pursuant to Rule 497(e)
Registration File Nos.: 2-53856
2-74980
SUPPLEMENT TO THE PROSPECTUSES OF:
MORGAN STANLEY DEAN WITTER LIQUID ASSET FUND (DATED OCTOBER 26, 1999)
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST (DATED
MARCH 29, 1999)
Effective on or about February 14, 2000, with respect to each of the
above-named prospectuses, the last sentence of the section entitled "How to Buy
Shares--Additional Purchase Information" is restated as follows:
If you are a customer of Dean Witter Reynolds or another authorized dealer
of the Fund's shares, you may have cash balances in your securities account
of $1,000 or more automatically invested in shares of the Fund on the next
business day after the balance is accrued in your account. Cash balances of
less than $1,000 may be automatically invested in Fund shares on a weekly
basis.
February 1, 2000
