<PAGE> PAGE 1
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<PAGE> PAGE 2
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<PAGE> PAGE 6
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<PAGE> PAGE 7
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<PAGE> PAGE 8
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<PAGE> PAGE 9
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<PAGE> PAGE 10
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<PAGE> PAGE 11
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<PAGE> PAGE 12
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<PAGE> PAGE 13
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<PAGE> PAGE 14
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<PAGE> PAGE 15
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<PAGE> PAGE 16
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<PAGE> PAGE 17
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<PAGE> PAGE 18
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SIGNATURE MARK E. BRADLEY
TITLE ASSISTANT TREASURER
<TABLE> <S> <C>
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<NET-ASSETS> 57735217
<DIVIDEND-INCOME> 388573
<INTEREST-INCOME> 112330
<OTHER-INCOME> (36138)
<EXPENSES-NET> 611579
<NET-INVESTMENT-INCOME> (146814)
<REALIZED-GAINS-CURRENT> 494835
<APPREC-INCREASE-CURRENT> 5656904
<NET-CHANGE-FROM-OPS> 6004925
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 663032
<NUMBER-OF-SHARES-REDEEMED> (641468)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 9362016
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 2480606
<OVERDISTRIB-NII-PRIOR> (12971)
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 260718
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 613664
<AVERAGE-NET-ASSETS> 53410416
<PER-SHARE-NAV-BEGIN> 17.74
<PER-SHARE-NII> (0.07)
<PER-SHARE-GAIN-APPREC> 2.15
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 19.82
<EXPENSE-RATIO> 2.53
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 022
<NAME> MFS INTERNATIONAL GROWTH AND INCOME FUND CLASS B
<MULTIPLIER> 1
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAY-31-2000
<PERIOD-START> JUN-01-1999
<PERIOD-END> NOV-30-1999
<INVESTMENTS-AT-COST> 49983403
<INVESTMENTS-AT-VALUE> 57613263
<RECEIVABLES> 346721
<ASSETS-OTHER> 108040
<OTHER-ITEMS-ASSETS> 3434823
<TOTAL-ASSETS> 61502847
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 3767630
<TOTAL-LIABILITIES> 3767630
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 47291813
<SHARES-COMMON-STOCK> 1269506
<SHARES-COMMON-PRIOR> 1312250
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> (159785)
<ACCUMULATED-NET-GAINS> 2975441
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 7627748
<NET-ASSETS> 57735217
<DIVIDEND-INCOME> 388573
<INTEREST-INCOME> 112330
<OTHER-INCOME> (36138)
<EXPENSES-NET> 611579
<NET-INVESTMENT-INCOME> (146814)
<REALIZED-GAINS-CURRENT> 494835
<APPREC-INCREASE-CURRENT> 5656904
<NET-CHANGE-FROM-OPS> 6004925
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 234107
<NUMBER-OF-SHARES-REDEEMED> (276851)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 9362016
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 2480606
<OVERDISTRIB-NII-PRIOR> (12971)
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 260718
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 613664
<AVERAGE-NET-ASSETS> 53410416
<PER-SHARE-NAV-BEGIN> 17.89
<PER-SHARE-NII> (0.07)
<PER-SHARE-GAIN-APPREC> 2.17
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 19.99
<EXPENSE-RATIO> 2.53
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000783740
<NAME> MFS SERIES TRUST X
<SERIES>
<NUMBER> 024
<NAME> MFS INTERNATIONAL GROWTH AND INCOME FUND CLASS I
<MULTIPLIER> 1
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAY-31-2000
<PERIOD-START> JUN-01-1999
<PERIOD-END> NOV-30-1999
<INVESTMENTS-AT-COST> 49983403
<INVESTMENTS-AT-VALUE> 57613263
<RECEIVABLES> 346721
<ASSETS-OTHER> 108040
<OTHER-ITEMS-ASSETS> 3434823
<TOTAL-ASSETS> 61502847
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 3767630
<TOTAL-LIABILITIES> 3767630
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 47291813
<SHARES-COMMON-STOCK> 3267
<SHARES-COMMON-PRIOR> 3270
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> (159785)
<ACCUMULATED-NET-GAINS> 2975441
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 7627748
<NET-ASSETS> 57735217
<DIVIDEND-INCOME> 388573
<INTEREST-INCOME> 112330
<OTHER-INCOME> (36138)
<EXPENSES-NET> 611579
<NET-INVESTMENT-INCOME> (146814)
<REALIZED-GAINS-CURRENT> 494835
<APPREC-INCREASE-CURRENT> 5656904
<NET-CHANGE-FROM-OPS> 6004925
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 255
<NUMBER-OF-SHARES-REDEEMED> (258)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 9362016
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 2480606
<OVERDISTRIB-NII-PRIOR> (12971)
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 260718
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 613664
<AVERAGE-NET-ASSETS> 53410416
<PER-SHARE-NAV-BEGIN> 18.08
<PER-SHARE-NII> 0.02
<PER-SHARE-GAIN-APPREC> 2.19
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 20.29
<EXPENSE-RATIO> 1.54
</TABLE>
34462
Item 77Q1
MFS SERIES TRUST X
CERTIFICATION OF AMENDMENT
TO THE DECLARATION OF TRUST
REDESIGNATION OF SERIES
Pursuant to Section 6.9 of the Amended and Restated Declaration of
Trust dated January 19, 1995, as amended (the "Declaration"), of MFS Series
Trust X, a business trust organized under the laws of The Commonwealth of
Massachusetts (the "Trust"), the undersigned Trustees of the Trust, being a
majority of the Trustees of the Trust, hereby redesignate an existing series of
Shares (as defined in the Declaration) as follows:
1. The series designated as MFS/Foreign & Colonial Emerging Markets
Equity Fund shall be redesignated as MFS Emerging Markets Equity
Fund.
Pursuant to Section 6.9(h) of the Declaration, this instrument shall be
effective upon the execution by a majority of the Trustees of the Trust.
IN WITNESS WHEREOF, a majority of the Trustees of the Trust have
executed this amendment, in one or more counterparts, all constituting a single
instrument, as an instrument under seal in The Commonwealth of Massachusetts, as
of this _____ day of _______________, ______.
- --------------------- --------------------
Richard B. Bailey Charles W. Schmidt
63 Atlantic Avenue 63 Claypit Hill Road
Boston, MA 02110 Wayland, MA 01778
- --------------------- --------------------
J. Atwood Ives Arnold D. Scott
17 West Cedar Street 20 Rowes Wharf
Boston, MA 02108 Boston, MA 02110
- --------------------- --------------------
Lawrence T. Perera Jeffrey L. Shames
18 Marlborough Street 38 Lake Avenue
Boston, MA 02116 Newton, MA 02159
- --------------------- --------------------
William J. Poorvu Elaine R. Smith
975 Memorial Drive 75 Scotch Pine Road
Cambridge, MA 02138 Weston, MA 02193
___________________
David B. Stone
282 Beacon Street
Boston, MA 02116
35003
Item 77Q1
MFS SERIES TRUST X
MFS SMALL CAP VALUE FUND
Pursuant to Section 9.2(b) of the Amended and Restated Declaration of
Trust, dated January 19, 1995, as amended, (the "Declaration"), of MFS Series
Trust X (the "Trust"), the undersigned, constituting a majority of the Trustees
of the Trust, do hereby certify that MFS Small Cap Value Fund, a series of the
Trust, has been terminated.
IN WITNESS WHEREOF, the undersigned have executed this certificate this
________ day of December, 1999.
- --------------------- --------------------
Richard B. Bailey Charles W. Schmidt
63 Atlantic Avenue 63 Claypit Hill Road
Boston, MA 02110 Wayland, MA 01778
- --------------------- --------------------
J. Atwood Ives Arnold D. Scott
17 West Cedar Street 20 Rowes Wharf
Boston, MA 02108 Boston, MA 02110
- --------------------- --------------------
Lawrence T. Perera Jeffrey L. Shames
18 Marlborough Street 38 Lake Avenue
Boston, MA 02116 Newton, MA 02159
- --------------------- --------------------
William J. Poorvu Elaine R. Smith
975 Memorial Drive 75 Scotch Pine Road
Cambridge, MA 02138 Weston, MA 02193
-------------------
David B. Stone
282 Beacon Street
Boston, MA 02116
