Driving Motivation (Step 2)
B1-IntermediateBNC LevelsCEFR LevelsProtectedSciencesStep 2StoriesTop Picks 0
ReadOasis Step 2 Doctor Harry Harlow made a difficult puzzle. At least he thought it was difficult. On a block of wood, he placed a metal catch called a hinge. A hinge is a piece of metal joined to a door. It allows the door to open and shut.... Read more
ReadOasis Step 3 Professor Harry Harlow thought that he had created a difficult puzzle. He placed a hinge on a block of wood. A hook held the hinge closed. A pin blocked the movement of the hook. To open the hinge you first had to remove the pin, then... Read more