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MFS(R) INTERMEDIATE INVESTMENT GRADE BOND FUND
MFS(R) RESEARCH BOND FUND
Supplement to the Current Prospectus
The description of portfolio managers under the "Management of the Funds -
Investment Adviser" section is hereby restated as follows:
Investment Grade Bond Fund James J. Calmas, a Vice President of the Adviser,
is the portfolio manager of the Fund. Mr.
Calmas has been employed by the Adviser since
1988 and has been the Fund's portfolio manager
since January 21, 1999.
Research Bond Fund Robert J. Manning, a Senior Vice President and
member of the Fixed Income Management Group of the
Adviser, has been employed as a portfolio manager
by the Adviser since 1984. Mr. Manning oversees
a committee of various fixed income research
analysts employed by the Adviser.
The date of this Supplement is January 21, 1999.
