Sam has been ill lately and so he has missed a lot of classes. His teachers have told him he’ll need to work very hare to ____ all the lost time.

  • make up for



Ancient cloth makers probably could not twist flax fibers until they had dipped the fibers into water to make them ____.
  • supple
Science progresses by building on what has come before; important findings thus form the basis of ____ experiments.
  • subsequent
People from all over the world are sent by their doctors to breath the pure, ____ air in this mountain region
  • invigorating