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MFS(R) MONEY MARKET FUND
MFS(R) CASH RESERVE FUND
SUPPLEMENT TO THE CURRENT PROSPECTUS
The section of the prospectus entitled "Principal Investment Strategies" is
hereby amended to add the following:
The funds may invest in municipal securities and participation interests in
municipal securities issued by banks when yield differentials make investment in
these securities attractive. Up to 20% of the fund's net assets may be invested
in these securities. Municipal securities are bonds or other debt obligations of
a U.S. state or political subdivision, such as a county, city, town, village, or
authority. Participation interests in municipal securities are interests in
holdings of municipal obligations backed by a letter of credit or guarantee from
the issuing bank. Because municipal securities may not exceed 20% of the fund's
net assets, all distributions of income from the municipal securities will be
reported as taxable income to shareholders.
The date of this Supplement is January 28, 2000.
