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Professor Smith and Professor Brown will _____ in giving the class lectures.

A. exchange      B. alter      C. shift      D. alternate

Professor Smith and Professor Brown will _____ in giving the class lectures.

A. exchange        B. alter            C. shift            D. alternate

 Professor Smith and Professor Brown will _____ in giving the class lectures.
      A. exchange              B. alter                C. shift            D. alternate

 Professor Smith and Professor Brown will _____ in giving the class lectures.

      A. exchange              B. alter                C. shift            D. alternate

. Professor Smith and Professor Brown will _____ in giving the class lectures.

A. exchange    B. alter    C. shift    D. alternate