1
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                  -------------

                                SCHEDULE 14D-1/A

                             TENDER OFFER STATEMENT
                                (AMENDMENT NO. 1)

                          PURSUANT TO SECTION 14(d)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
                                       AND
                                 SCHEDULE 13D/A
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                                (AMENDMENT NO. 1)

                        COMPUTER LANGUAGE RESEARCH, INC.
                            (NAME OF SUBJECT COMPANY)

                             SABRE ACQUISITION, INC.
                                       AND
                             THE THOMSON CORPORATION
                                    (BIDDERS)

                          COMMON STOCK, $.01 PAR VALUE
                         (TITLE OF CLASS OF SECURITIES)

                                    20519510
                      (CUSIP NUMBER OF CLASS OF SECURITIES)
                                  -------------

                             MICHAEL S. HARRIS, ESQ.
                             THE THOMSON CORPORATION
                        METRO CENTER AT ONE STATION PLACE
                           STAMFORD, CONNECTICUT 06902
                     (NAME, ADDRESS AND TELEPHONE NUMBER OF
                      PERSON AUTHORIZED TO RECEIVE NOTICES
                    AND COMMUNICATIONS ON BEHALF OF BIDDERS)

                                    COPY TO:
                             DAVID W. HELENIAK, ESQ.
                               SHEARMAN & STERLING
                              599 LEXINGTON AVENUE
                            NEW YORK, NEW YORK 10022
                            TELEPHONE: (212) 848-4000


                                FEBRUARY 4, 1998

                                PAGE 1 OF 8 PAGES
                       AN EXHIBIT INDEX APPEARS ON PAGE 8.
   2
CUSIP No. 20519510

- --------------------------------------------------------------------------------
1.      Name of Reporting Persons
            S.S. or I.R.S. Identification Nos. of Above Person

            SABRE ACQUISITION, INC.
- --------------------------------------------------------------------------------
2.      Check the Appropriate Box if a Member of Group
        (a) /X/
        (b) / /
- --------------------------------------------------------------------------------
3.      SEC Use only
- --------------------------------------------------------------------------------
4.      Sources of Funds
        WC
- --------------------------------------------------------------------------------
5.      Check if Disclosure of Legal Proceedings is Required Pursuant to Item
        2(d) or 2(f) / /
- --------------------------------------------------------------------------------
6.      Citizen or Place of Organization

        Delaware
- --------------------------------------------------------------------------------
7.      Aggregate Amount Beneficially Owned by Each Reporting Person

        10,786,812 Shares which may be deemed beneficially owned pursuant to the
            Stock Purchase Agreement described herein.
- --------------------------------------------------------------------------------
8.      Check if the Aggregate Amount in Row (7) Excludes Certain Shares / /
- --------------------------------------------------------------------------------
9.      Percent of Class Represented by Amount in Row (7)

        74.6%
- --------------------------------------------------------------------------------
10.     Type of Reporting Person

        CO
- --------------------------------------------------------------------------------


                                Page 2 of 8 Pages
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CUSIP No. 20519510
- --------------------------------------------------------------------------------
1.      Name of Reporting Persons
            S.S. or I.R.S. Identification Nos. of Above Person

            THE THOMSON CORPORATION
- --------------------------------------------------------------------------------
2.      Check the Appropriate Box if a Member of Group
        (a) /X/
        (b) / /
- --------------------------------------------------------------------------------
3.      SEC Use only
- --------------------------------------------------------------------------------
4.      Sources of Funds
        WC
- --------------------------------------------------------------------------------
5.      Check if Disclosure of Legal Proceedings is Required Pursuant to Item
        2(d) or 2(f) / /
- --------------------------------------------------------------------------------
6.      Citizen or Place of Organization

        Ontario, Canada
- --------------------------------------------------------------------------------
7.      Aggregate Amount Beneficially Owned by Each Reporting Person

        10,786,812 Shares which may be deemed beneficially owned pursuant to the
            Stock Purchase Agreement described herein.
- --------------------------------------------------------------------------------
8.      Check if the Aggregate Amount in Row (7) Excludes Certain Shares / /
- --------------------------------------------------------------------------------
9.      Percent of Class Represented by Amount in Row (7)

        74.6%
- --------------------------------------------------------------------------------
10.     Type of Reporting Person

        CO
- --------------------------------------------------------------------------------


                                Page 3 of 8 Pages
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      This Amendment No. 1 to the Tender Offer Statement on Schedule 14D-1 and
Amendment No. 1 to Schedule 13D (the "Schedule 14D-1") relates to the offer by
Sabre Acquisition, Inc., a Delaware corporation ("Purchaser") and a wholly owned
subsidiary of The Thomson Corporation, a corporation organized under the laws of
Ontario, Canada ("Parent"), to purchase all outstanding shares of Common Stock,
par value $.01 per share (the "Shares"), of Computer Language Research, Inc., a
Texas corporation (the "Company"), at a price of $22.50 per Share, net to the
seller in cash, upon the terms and subject to the conditions set forth in
Purchaser's Offer to Purchase dated January 16, 1998 (the "Offer to Purchase")
and in the related Letter of Transmittal, copies of which were attached to the
Schedule 14D-1 as Exhibits (a)(1) and (a)(2) thereto, respectively. The Schedule
14D-1 was initially filed with the Securities and Exchange Commission on January
16, 1998.

      Capitalized terms used but not defined herein have the meanings ascribed
to such terms in the Offer to Purchase and the Schedule 14D-1.

ITEM 3. PAST CONTRACTS, TRANSACTIONS OR NEGOTIATIONS WITH THE SUBJECT COMPANY

      Item 3(b) of the Schedule 14D-1 is hereby amended by amending the Offer to
Purchase as follows: delete the term "the Company" from the fourth sentence of
the carryover paragraph on pages 11-12 of Section 7 ("Certain Information
Concerning the Company") of the Offer to Purchase.

ITEM 7. CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT TO
        THE SUBJECT COMPANY'S SECURITIES.

      Item 7 of the Schedule 14D-1 is hereby amended and supplemented by
amending the Offer to Purchase as follows: add to the end of Section 10
("Background of the Offer; Contracts with the Company; the Merger Agreement and
Stock Purchase Agreement -- The Stock Purchase Agreement") of the Offer to
Purchase on page 27 thereof the following paragraph:

            The Stock Purchase Agreement provides that except as otherwise
      provided therein, all costs and expenses incurred in connection with the
      transactions contemplated by the Stock Purchase Agreement shall be paid by
      the party incurring such costs and expenses; provided, that if the closing
      contemplated by the Stock Purchase Agreement occurs, Purchaser shall,
      promptly following any request from the Majority Stockholders, reimburse
      the Majority Stockholders for up to an aggregate of $350,000 of their
      reasonable fees and expenses (including reasonable fees and expenses of
      counsel) incurred in connection with the Stock Purchase Agreement or the
      Merger Agreement or the transactions contemplated thereby, including,
      without limitation, any employment arrangements contemplated thereby; and
      provided, further, that Purchaser shall pay any stock transfer taxes
      relating to the purchase and sale of the Shares pursuant to the Stock
      Purchase Agreement (including, without limitation, pursuant to the Offer
      or the Merger).


                                Page 4 of 8 Pages
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ITEM 10. ADDITIONAL INFORMATION.

      Item 10(f) of the Schedule 14D-1 is hereby amended by amending the Offer
to Purchase as follows:

      (a) Delete from clause (iii) of the first paragraph of Section 14
      ("Certain Conditions of the Offer") on page 31 of the Offer to Purchase
      the phrase "acceptance for payment of Shares" and replace such phrase with
      the term "Expiration Date."

      (b) Restate in its entirety the first paragraph of Section 2 ("Acceptance
      for Payment and Payment for Shares") on page 4 of the Offer to Purchase as
      follows:

            2. ACCEPTANCE FOR PAYMENT AND PAYMENT FOR SHARES. Upon the terms and
      subject to the conditions of the Offer (including, if the Offer is
      extended or amended, the terms and conditions of any such extension or
      amendment), Purchaser will accept for payment, and will pay for, all
      Shares validly tendered prior to the Expiration Date and not properly
      withdrawn promptly after the occurrence of the Expiration Date. Subject to
      applicable rules of the Commission and the terms of the Merger Agreement,
      Purchaser expressly reserves the right to delay acceptance for payment of
      Shares pending receipt of any regulatory approvals specified in Section 15
      or in order to comply in whole or in part with any other applicable law.


                                Page 5 of 8 Pages
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      After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.


                                    SABRE ACQUISITION, INC.

Dated:  February 4, 1998

                                    By /s/ MICHAEL S. HARRIS
                                       -----------------------------------------
                                       Name:  Michael S. Harris
                                       Title: President


                                Page 6 of 8 Pages
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      After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.


                                    THE THOMSON CORPORATION

Dated:  February 4, 1998

                                    By /s/ MICHAEL S. HARRIS
                                       -----------------------------------------
                                       Name:  Michael S. Harris
                                       Title: Assistant Secretary


                                Page 7 of 8 Pages
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                                  EXHIBIT INDEX


PAGE IN SEQUENTIAL EXHIBIT NO. NUMBERING SYSTEM - ----------- ---------------- (a)(1) Form of Offer to Purchase dated January 16, 1998........ * (a)(2) Form of Letter of Transmittal........................... * (a)(3) Form of Notice of Guaranteed Delivery................... * (a)(4) Form of Letter from Purchaser to Brokers, Dealers, Commercial Banks, Trust Companies and Other Nominees.... * (a)(5) Form of Letter from Brokers, Dealers, Commercial Banks, Trust Companies and Nominees to Clients.......... * (a)(6) Form of Guidelines for Certification of Taxpayer Identification Number on Substitute Form W-9............ * (a)(7) Summary Advertisement as published in The Wall Street Journal on January 16, 1998...................... * (a)(8) Press Release issued jointly by Parent and the Company on January 13, 1998............................. * (a)(9) Consolidated Financial Statements of Parent as set forth in Parent's 1996 Annual Report to Shareholders.... * (c)(1) Agreement and Plan of Merger, dated as of January 12, 1998, among Parent, Purchaser and the Company........... * (c)(2) Stock Purchaser Agreement, dated as of January 12, 1998, among Parent, Purchaser and certain Shareholders of the Company................................................. * (c)(3) Form of Retention Agreement between the Company and M. Brian Healy............................................. * (c)(4) Form of Retention Agreement between the Company and Francis W. Winn......................................... * (c)(5) Form of Retention Agreement between the Company and Douglas H. Gross........................................ * (c)(6) Form of Retention Agreement between the Company and Stephen T. Winn......................................... *
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